bromochloroacetic-acid and Melanoma

Topics: Aged; Carcinoma, Medullary; Carcinoma, Squamous Cell; Diagnosis, Differential; Gastrectomy; Humans; Keratins; Lymphoma; Melanoma; Middle Aged; Neoplasm Staging; Retrospective Studies; RNA, Viral; Stomach Neoplasms

Topics: Aged; Aged, 80 and over; Carcinoma, Squamous Cell; Cell Proliferation; Female; Head and Neck Neoplasms; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Nose Neoplasms; S100 Proteins; Skin Neoplasms; Squamous Cell Carcinoma of Head and Neck

Miscellaneous primary tumors of the uterine cervix are rare. Markers which can be utilized to detect these tumors are very few and in most cases, have not been clinically validated. The information provided in this article will help in developing strategies to discover novel markers and initiate translational research in this ignored area. Based on the reported studies, cytokeratin markers are common in many tumors and few of these rare cancers demonstrate human papilloma-virus (HPV) and Epstein Bar virus (EBV) infection. Due to the very low prevalence of these tumors, epidemiological studies have not been conducted and the etiology of these tumors is largely unknown.

Topics: Biomarkers, Tumor; Carcinoma; Cell Transformation, Neoplastic; Female; Humans; Immunohistochemistry; Keratins; Lipoma; Melanoma; Neurilemmoma; Rare Diseases; Sarcoma; Uterine Cervical Neoplasms

The use of DNA microarray technology in biomedical research has dramatically increased during the past years. In the present report, we provide an overview on the basic DNA microarray technology and biostatistical methods for gene expression analysis. A focus is then put on its applications in dermatological research. In recent years, a series of gene expression studies have been performed for various dermatological diseases, such as malignant melanoma, psoriasis and lupus erythematosus. These analyses have identified interesting target genes as well as putative disease susceptibility loci. However, further functional studies will be needed for a more complete understanding of the pathogenesis of these diseases. This may be performed by means of the recently developed RNA interference technology. Besides its role in large-scale gene expression studies, DNA microarray technology has proved to be a valuable tool for genomic screens of genetic alterations, e.g. single nucleotide polymorphisms. These play a role in tumour development and progression, and also function as genetic markers for disease susceptibility. Taken together, DNA microarray technology opens enormous perspectives for dermatologists. It may help us understand the complex pathogenesis of a wide variety of dermatologic diseases and identify their genetic background.

Topics: Cell Differentiation; Gene Expression Profiling; Humans; Hybridization, Genetic; Keratinocytes; Keratins; Melanoma; Oligonucleotide Array Sequence Analysis; Psoriasis; RNA, Messenger; Skin Neoplasms; Ultraviolet Rays

A 63-year-old patient with a malignant melanoma of the uterine cervix is described. Subtle epitheliotropism of the neoplastic cells within the endocervical columnar epithelium suggested melanoma in situ and the possibility of a primary uterine cervical melanoma, despite a negative anti-S-100 protein immunohistochemical stain. An exhaustive clinical workup, and ultimately, complete autopsy failed to reveal any other primary tumor site, and the diagnosis of melanoma was confirmed by histology and immunohistochemistry on the hysterectomy specimen. A world literature review revealed 54 previously reported cases of uterine cervical melanoma of which 43 had been reported as primary uterine cervical melanoma. A true intraepithelial melanocytic component was found in only 14 of those cases, however, and none of those reports illustrated this with the clarity with which it was seen in the endocervical glandular and surface columnar epithelium of the present case. Primary uterine cervical melanoma is usually discovered at an advanced stage and is no longer amenable to curative therapy. Even when this tumor is discovered early, however, the diagnosis may be unnecessarily delayed if the often subtle interaction of the neoplastic cells with the benign cervical squamous or glandular epithelium is not appreciated, or if the possibility of malignant melanoma is not entertained based on other histologic or immunohistologic characteristics of the tumor cells.

Topics: Actins; Desmin; Epithelium; Fatal Outcome; Female; Humans; Hysterectomy; Immunohistochemistry; Keratins; Melanocytes; Melanoma; Melanoma, Amelanotic; Middle Aged; Mucin-1; Neoplasm Metastasis; Neoplasm Recurrence, Local; S100 Proteins; Uterine Cervical Neoplasms; Uterine Hemorrhage

The long-range goal of our research is to develop intervention strategies based on newly discovered biologic mechanisms responsible for the invasive dissemination of metastatic uveal melanoma. To accomplish this goal, we have focused on the biologic relevance of novel marker proteins contributing to the uveal melanoma metastatic phenotype. The expression of vimentin intermediate filaments (IFs), a mesenchymal marker, is typical of melanomas, whereas carcinomas typically express keratin IFs, which are markers for epithelia. Thus, cells that coexpress both IFs are regarded as "interconverted" in that they display both mesenchymal and epithelial phenotypes. Although the biologic functions of IFs have remained enigmatic, there is substantial support to suggest that the significance of vimentin/keratin coexpression is linked with poor patient outcome in cutaneous melanoma. Our data demonstrate that human uveal melanoma cell lines (isolated from primary choroidal or ciliary body melanomas and from foci of metastatic uveal melanoma to the liver), which contain predominant populations of cells that coexpress vimentin/keratins 8 and 18 (keratins 8,18) IFs, were 6-fold more invasive through collagenous extracellular matrices in vitro, compared with uveal melanoma cells expressing vimentin only, and were 8- to 13-fold more invasive than normal uveal melanocytes. Colocalization of vimentin/keratins 8,18 in cell cultures was corroborated by immunohistochemistry in histologic sections of tumors from which the cell lines were derived. Minor populations of these cells also coexpressed keratins 13 and 17. Experimental down-regulation of the predominant keratins 8,18 in the interconverted cells, using 16-mer antisense oligonucleotides, resulted in a significant decrease in the migratory ability of the cells-similar to levels achieved by cells positive only for vimentin. These findings provide justification for additional studies of the association between coexpression of IFs vimentin/keratins 8,18 and uveal melanoma metastasis.

Topics: Antisense Elements (Genetics); Biomarkers, Tumor; Choroid Neoplasms; Ciliary Body; Forecasting; Humans; Intermediate Filament Proteins; Keratins; Liver Neoplasms; Melanoma; Neoplasm Invasiveness; Phenotype; Time Factors; Tumor Cells, Cultured; Uveal Neoplasms

The morphological spectrum of malignant melanoma is broad. Unusual stromal changes can distract pathologists from the correct diagnosis. Fibroblastic, chondroid, osteoid, and myxoid stroma have been documented in melanomas. Myxoid melanoma is problematic--introducing carcinomas and soft tissue sarcomas into the differential diagnosis. This review examines the clinicopathologic aspects of myxoid malignant melanoma, with emphasis on its differential diagnosis.

Topics: Adult; Aged; Diagnosis, Differential; Female; Humans; Keratins; Male; Melanins; Melanoma; Middle Aged; Mucins; S100 Proteins; Skin; Skin Neoplasms; Stromal Cells

While not all circulating tumor cells survive, one could postulate that patients with circulating tumor cells might be candidates for adjuvant chemotherapy because of the risk of relapse. Recently, reverse transcriptase-polymerase chain reaction (RT-PCR) for the detection of circulating tumor cells has been suggested as a potential technique for staging of cancer. In malignant melanoma, the detection of circulating melanoma cells by tyrosinase RT-PCR correlated with the clinical stage of patients and was an independent prognostic factor for recurrence. A strong association was found between the detection of neuroblastoma cells in circulation by tyrosine hydroxylase RT-PCR with bone marrow micrometastasis. This method may be of use to identify early signs of relapse in disease-free patients. In prostatic cancer, the frequency of positivity for detection of circulating tumor cells in peripheral blood by PSA RT-PCR increased with tumor stages but a significant proportion of patients with metastatic disease were negative. The prognostic significance of the detection of tumor cell in blood in other epithelial tumors is not established and will require further long-term follow-up study.

Topics: alpha-Fetoproteins; Biomarkers, Tumor; Genes, ras; Humans; Keratins; Melanoma; Monophenol Monooxygenase; Neoplasms; Neoplastic Cells, Circulating; Point Mutation; Polymerase Chain Reaction; RNA; Tyrosine 3-Monooxygenase

Molecular genetic analyses during the past half-decade have brought unexpected insights into the molecular defects underlying a wide variety of abnormal skin phenotypes. Highlights of the efforts in the past year include the identification of mutations in an epidermal transglutaminase gene in lamellar ichthyosis as well as mutations in an additional five keratin genes causing four different abnormal phenotypes, and mutations in beta 4 integrin and bullous pemphigoid antigen 2 genes in junctional epidermolysis bullosa and in the p16NK-4a gene in 50% of kindreds with familial melanoma.

Topics: Epidermolysis Bullosa, Junctional; Humans; Ichthyosis, Lamellar; Keratins; Melanoma; Skin Diseases; Skin Neoplasms

Immunohistology was performed on 84 paraffin-embedded surgical specimens of malignant melanomas (MM) from a total of 74 patients. The series consisted of 62 cutaneous primary tumors and 22 (partly selected) secondary manifestations (9 cutaneous recurrences and 13 metastases). In 4 patients with lymph node MM infiltrates, clinical investigations failed to identify a cutaneous primary tumor. In the primary and secondary manifestations respectively, the following proportions of immunohistologically positive cases were recorded: vimentin 100% each, S100-protein 95% each, NSE 87%/77%, HMB45 97%/64%, NKI/C3 97%/95%, cytokeratins (CK) (antibodies KL1, CAM5.2 and 35 beta H11) 0%/23%. Four of the 5 CK-positive lesions belonged to 3 patients in whom MM had occurred at first or exclusively as a lymph node infiltration. These findings confirm the results of other authors who report that positive staining results for CK can be expected in paraffin sections of secondary manifestations of MM in up to 10% of cases in large, nonselected series. This phenomenon appears, however, to be rare in primary cutaneous MM.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Diagnosis, Differential; Female; Humans; Immunoenzyme Techniques; Keratins; Lymph Nodes; Lymphatic Metastasis; Male; Melanoma; Middle Aged; Neoplasm Recurrence, Local; Neoplasms, Unknown Primary; Skin; Skin Neoplasms

This review discusses several commonly used lineage-directed antibodies, including those to cytokeratins, vimentin, glial fibrillary acidic protein, neurofilaments, desmin, actin, leukocyte common antigen, and melanoma-specific antigen. Discussion is particularly directed to issues of antibody sensitivity and specificity, with several confusing and/or potentially beneficial examples of cross-lineage antigenic co-expression cited. The value of using limited panels composed of antibodies with complementary specificities is also emphasized.

Topics: Actins; Antibodies; Antibody Specificity; Antigens, Differentiation; Cell Line; Cytoskeleton; Desmin; Glial Fibrillary Acidic Protein; Histocompatibility Antigens; Humans; Immunohistochemistry; Intermediate Filaments; Keratins; Leukocyte Common Antigens; Melanoma; Vimentin

The development and refinement of immunohistochemical methodologies over the past decade has had a major impact in many different areas of diagnostic pathology. The generation of increasing numbers of well-characterized polyclonal antisera and monoclonal antibodies directed to a variety of antigenic determinants has made the phenotyping of neoplasms a reality. The results of such immunohistochemical analyses have provided an important starting point for the further workup and management of patients with undifferentiated or poorly differentiated malignant neoplasms of unknown origin. It should also be apparent, however, that the results of immunohistochemical analyses in such clinical settings are subject to a large number of variables and that these procedures must be controlled rigorously. The results of extensive performance testing, particularly with new reagents, must be available in order to establish their specificities and sensitivities under different conditions of tissue fixation and processing. Such studies not only will establish more precise and reproducible diagnostic criteria but also will be important for the definition of new clinical and pathological entities and for the characterization of novel prognostic parameters.

Topics: Antibodies, Monoclonal; Antibodies, Neoplasm; Antigens, Neoplasm; Antigens, Surface; Carcinoembryonic Antigen; Cell Differentiation; Cytoskeletal Proteins; Desmoplakins; Epithelium; Hematopoietic Stem Cells; Immunologic Techniques; Keratins; Melanoma; Membrane Proteins; Mucin-1; Neoplasms

Topics: Adenocarcinoma; Adenoma, Islet Cell; Animals; Antibodies, Monoclonal; Breast Neoplasms; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Cytoskeletal Proteins; Desmoplakins; Desmosomes; Electrophoresis, Polyacrylamide Gel; Granulosa Cell Tumor; Humans; Immunosorbent Techniques; Intermediate Filament Proteins; Intermediate Filaments; Keratins; Kidney Neoplasms; Lung Neoplasms; Melanoma; Membrane Proteins; Meningioma; Mesothelioma; Microscopy, Electron; Microscopy, Fluorescence; Neoplasms; Neurosecretory Systems; Skin Neoplasms

Topics: Adenocarcinoma; Carcinoma; Diagnosis, Differential; Endocrine System Diseases; Humans; Immunoenzyme Techniques; Keratins; Lymphoma; Melanoma; Neoplasm Invasiveness; Neoplasms, Germ Cell and Embryonal; Skin Neoplasms; Sweat Gland Neoplasms

A panel of monoclonal antibodies to human intermediate filament proteins was tested on an unselected series of 246 neoplasms. The antibody panel includes two different anti-cytokeratin antibodies, an anti-vimentin antibody, and an anti-neurofilament antibody (Gown and Vogel, Am J Pathol 114:309, 1984). The studies were done on Carnoy's or methacarn-fixed, paraffin-embedded tissue. When used as a panel, they can unequivocally distinguish carcinomas, melanomas, and lymphomas. All carcinomas react with at least one of the anti-cytokeratin antibodies, and carcinomas can be subtyped based upon the pattern of reactivity with the two anti-cytokeratin antibodies. Melanomas react only with the anti-vimentin antibody, and lymphomas react with none of the antibodies. Neural and neuroendocrine tumors can be identified with the anti-neurofilament antibody. A minority of neoplasms, including lymphomas, seminomas, and some sarcomas, do not react with any of the antibodies. These antibodies are reliable diagnostic reagents that are useful in distinguishing different categories of human tumors.

Topics: Antibodies, Monoclonal; Antibody Specificity; Carcinoma; Cytoskeleton; Humans; Intermediate Filament Proteins; Keratins; Melanoma; Neoplasms; Nervous System Neoplasms; Vimentin

Immunohistochemistry of intermediate filaments (IF) is a new and important way to evaluate the epithelial, mesenchymal, muscular, glial, or neural differentiation in tumors. This is based on the stable cell-type-specific expression of IF proteins in normal and neoplastic tissues. Immunohistochemical studies with antibodies to intermediate filaments have also given new perspectives in the histogenesis and biologic nature of many tumors. This article reviews both the recent findings and the authors' experience in the use of intermediate filament antibodies in tumor diagnosis and classification.

Topics: Adenocarcinoma; Antibodies, Neoplasm; Carcinoma, Squamous Cell; Desmin; Diagnosis, Differential; Glial Fibrillary Acidic Protein; Histocytochemistry; Humans; Immunochemistry; Keratins; Melanoma; Mesothelioma; Microfilament Proteins; Microscopy, Electron; Neoplasm Proteins; Neoplasms; Nervous System Neoplasms; Sarcoma; Soft Tissue Neoplasms; Thyroid Neoplasms; Urinary Bladder Neoplasms; Vimentin

Topics: Carcinoembryonic Antigen; Carcinoma; Diagnosis, Differential; Female; Histocytochemistry; Humans; Immunoenzyme Techniques; Immunologic Techniques; Keratins; Melanoma; Mesenchymoma; Paget Disease, Extramammary; Protein Precursors; S100 Proteins; Vulvar Neoplasms

Topics: Acetylcholine; Animals; Anura; Catechol Oxidase; Cell Differentiation; Cells, Cultured; Cricetinae; Cyclic AMP; Cytoplasmic Granules; Dendrites; Keratins; Melanins; Melanocyte-Stimulating Hormones; Melanocytes; Melanoma; Microtubules; Organoids; Phagocytosis; RNA Viruses; Skin

Currently, the diagnostic sensitivity of malignant liver mass biopsies is an important problem in the definitive diagnosis. In this study, we aimed to investigate the role of selective peripheral approach to lesion biopsies for diagnostic sensitivity of liver masses.. Between June 2007 and March 2011, totally 88 patients (50 male, 38 female), referred to our Interventional Radiology Department for sonographically guided Tru-cut biopsies for liver lesions, were examined.All biopsies were performed by an experienced radiologist with an 18-gauge Tru-cut biopsy needle with a spring-loaded biopsy gun under sonographic guidance. We describe two locations (peripheral and central) for liver lesions, with the inner 2/3 part of the mass as central and the outer 1/3 part as peripheral. We obtained biopsy from both of these locations, and samples were transferred to the Pathology Department separately.. According to pathological and immunohistochemistry studies, there were 42 hepatocellular carcinomas and 46 metastases. All of the metastatic tumors were stained by cytokeratin (10 lung adenocarcinoma, 15 breast adenocarcinoma, 16 gastrointestinal tract, 4 prostate, and 1 malignant melanoma of these 46 metastases were reported as primary). According to histopathological results, diagnostic sensitivity was 97.7% in peripherally located biopsies and 86.3% in biopsies taken from the center of the masses (p=0.0063).. Selective peripheral biopsy approach in Tru-cut biopsies of liver lesions has better sensitivity rates for histopathologic diagnosis compared to the centrally located and random biopsies.

Topics: Adenocarcinoma; Adult; Aged; Biomarkers, Tumor; Biopsy, Needle; Breast Neoplasms; Carcinoma, Hepatocellular; Creatine Kinase; Diagnosis, Differential; Female; Gastrointestinal Neoplasms; Humans; Keratins; Liver Cirrhosis; Liver Neoplasms; Lung Neoplasms; Male; Melanoma; Middle Aged; Prostatic Neoplasms; Sensitivity and Specificity; Skin Neoplasms

Cutaneous squamomelanocytic tumor (SMT) is an exceedingly rare cutaneous malignancy characterized by the presence of both squamous cell carcinoma and malignant melanoma within a single tumor. SMT typically presents clinically as keratotic skin papulonodules, most commonly occurring on the face, scalp, or other sun-exposed areas of middle-aged to elderly White male patients. Owing to the rare nature of this tumor, the histogenesis and prognosis remain relatively unclear. Histopathological examination of the tangential biopsy revealed an invasive cutaneous malignancy consisting of 2 distinct yet closely associated atypical cell populations: (1) a population of atypical squamoid epithelial cells arranged in cords and keratin pearls and (2) a population consisting of atypical, spindled cells with fine melanin pigment arranged in confluent sheets. Both populations of atypical cells emanated in an invasive pattern from the underside of the overlying epidermis into the deep dermis. Squamomelanocytic tumors are among the rarer types of collision tumors between 2 malignant lesions as most are basomelanocytic. For most reported SMTs, the melanoma population comprises epithelioid cell morphology, whereas our tumor is composed of spindled cell morphology. In this article, we exemplify a unique case of SMT in an 87-year-old male patient.

Topics: Aged; Aged, 80 and over; Humans; Immunohistochemistry; Keratins; Male; Melanins; Melanoma; Middle Aged; Skin Neoplasms

Keratinocytes constitute a major part of the melanoma microenvironment, considering their protective role towards melanocytes in physiological conditions. However, their interactions with tumor cells following melanomagenesis are still unclear.. We used two in vitro models (melanoma-conditioned media and indirect co-culture of keratinocytes with melanoma cells on Transwell inserts) to activate immortalized keratinocytes towards cancer-associated ones. Western Blotting and qPCR were used to evaluate keratinocyte markers and mediators of cell invasiveness on protein and mRNA expression level respectively. The levels and activity of proteases and cytokines were analysed using gelatin-FITC staining, gelatin zymography, chemiluminescent enzymatic test, as well as protein arrays. Finally, to further study the functional changes influenced by melanoma we assessed the rate of proliferation of keratinocytes and their invasive abilities by employing wound healing assay and the Transwell filter invasion method.. HaCaT keratinocytes activated through incubation with melanoma-conditioned medium or indirect co-culture exhibit properties of less differentiated cells (downregulation of cytokeratin 10), which also prefer to form connections with cancer cells rather than adjacent keratinocytes (decreased level of E-cadherin). While they express only a small number of cytokines, the variety of secreted proteases is quite prominent especially considering that several of them were never reported as a part of secretome of activated keratinocytes' (e.g., matrix metalloproteinase 3 (MMP3), ADAM metallopeptidase with thrombospondin type 1 motif 1). Activated keratinocytes also seem to exhibit a high level of proteolytic activity mediated by MMP9 and MMP14, reduced expression of TIMPs (tissue inhibitor of metalloproteinases), upregulation of ERK activity and increased levels of MMP expression regulators-RUNX2 and galectin 3. Moreover, cancer-associated keratinocytes show slightly elevated migratory and invasive abilities, however only following co-culture with melanoma cells on Transwell inserts.. Our study offers a more in-depth view of keratinocytes residing in the melanoma niche, drawing attention to their unique secretome and mediators of invasive abilities, factors which could be used by cancer cells to support their invasion of surrounding tissues. Video abstract.

Topics: Cadherins; Core Binding Factor Alpha 1 Subunit; Culture Media, Conditioned; Cytokines; Fluorescein-5-isothiocyanate; Galectin 3; Gelatin; Humans; Keratinocytes; Keratins; Matrix Metalloproteinase 14; Matrix Metalloproteinase 3; Matrix Metalloproteinase 9; Melanoma; RNA, Messenger; Thrombospondins; Tissue Inhibitor of Metalloproteinases

Clear cell sarcoma of soft tissue (CCSST) and conventional malignant melanoma (MM) are rare and aggressive tumours with similarities in morphology and the expression of melanocytic markers.. We established two CCSST cell lines (FU-CCSST-1 and FU-CCSST-2) from soft tissues of the patella and supraclavicular. A MM cell line (FU-MM-1) was established from lymph node metastases of subungual malignant melanoma.. FU-CCSST-2 cells were transplantable to immunodeficient mice. Immunohistochemical studies demonstrated tumour cells were negative for cytokeratin AE1/AE3 and positive for S100 protein, HMB45, Melan-A, CD146 and SOX10 in all specimens. FU-CCSST-1 and FU-CCSST-2 harboured t(12;22)(q13;q12) translocations with expression of the EWSR1/ATF1 fusion gene. FU-MM-1 demonstrated loss of the short arm of chromosome 9 and harboured wild-type BRAF (codon 469 and 600) and NRAS (codon 12, 13 and 61).. We report the establishment and characterisation of CCSST and MM cell lines that may have utility in the study of pathogenic mechanisms and development of novel therapeutic reagents.

Topics: Animals; CD146 Antigen; Cell Line; Humans; Keratins; MART-1 Antigen; Melanoma; Melanoma, Cutaneous Malignant; Mice; Proto-Oncogene Proteins B-raf; S100 Proteins; Sarcoma, Clear Cell

To evaluate the distribution of the PAX8 transcription factor protein in ocular tissues and to investigate if immunohistochemical stains for this biomarker are useful in the diagnosis of intraocular tumors.. Observational case series.. Excision and cytologic analysis specimens of 6 ciliary body epithelial neoplasms, 2 iris epithelial neoplasms, 3 retinal pigment epithelial neoplasms, 3 intraocular medulloepitheliomas, 15 uveal melanomas, and 5 uveal melanocytomas.. Hematoxylin-eosin and PAX8 immunohistochemical stains were performed on all specimens. In appropriate cases, bleached preparations and other immunohistochemical stains, including AE1/AE3 cytokeratin, Lin28A, and CD45, were performed.. Distribution of PAX8 expression in normal and neoplastic tissue.. Strong nuclear PAX8 expression was observed in the normal corneal epithelium, iris sphincter pupillae muscle, iris pigment epithelium and dilator muscle complex, nonpigmented and pigmented epithelia of the ciliary body, lens epithelium, and a subset of retinal neurons. The normal retinal pigment epithelium and uveal melanocytes did not stain for PAX8. The ciliary body epithelial and neuroepithelial tumors (adenoma, adenocarcinoma, and medulloepithelioma) showed uniform strong nuclear PAX8 immunoreactivity. All melanocytic tumors (iris melanoma, ciliary-choroidal melanoma, and melanocytoma) and retinal pigment epithelial neoplasms showed negative results for PAX8. A subset of tumor-associated lymphocytes, most prominent in uveal melanoma, showed positive results for PAX8. The uniformity of the PAX8 staining was superior to the variable cytokeratin staining in the ciliary epithelial neoplasms and the variable Lin28A staining in malignant medulloepithelioma. The veracity of PAX8 staining was equally as robust on cytologic analysis and open-flap biopsy specimens of ciliary epithelial and iris epithelial neoplasms, melanocytoma, and melanoma.. PAX8 has proven to be a very useful diagnostic marker in a select group of adult intraocular tumors, and we highly recommend its inclusion in diagnostic antibody panels of morphologically challenging intraocular neoplasms.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Ciliary Body; Eye Neoplasms; Female; Humans; Immunohistochemistry; Iris Neoplasms; Keratins; Leukocyte Common Antigens; Male; Melanoma; Middle Aged; Neoplasms, Glandular and Epithelial; PAX8 Transcription Factor; Retinal Neoplasms; Retinal Pigment Epithelium; RNA-Binding Proteins; Uveal Neoplasms

Keratins (KRTs), the intermediate filament-forming proteins of epithelial cells, are extensively used as diagnostic biomarkers in cancers and associated with tumorigenesis and metastasis in multiple cancers. However, the diverse expression patterns and prognostic values of KRTs in melanoma have yet to be elucidated. In the current study, we examined the transcriptional and clinical data of KRTs in patients with melanoma from GEO, TCGA, ONCOMINE, GEPIA, cBioPortal, TIMER and TISIDB databases. We found that the mRNA levels of KRT1/2/5/6/8/10/14/15/16/17 were significantly differential expressed between primary melanoma and metastatic melanoma. The expression levels of KRT1/2/5/6/10/14/15/16/17 were correlated with advanced tumor stage. Survival analysis revealed that the high transcription levels of KRT1/5/6/14/15/16/17 were associated with low overall survival in melanoma patients. GSEA analysis indicated that the most involved hallmarks pathways were P53 pathway, KRAS signaling, estrogen response early and estrogen response late. Furthermore, we found some correlations among the expression of KRTs and the infiltration of immune cells. Our study may provide novel insights for the selection of prognostic biomarkers for melanoma.

Topics: Biomarkers, Tumor; Databases, Nucleic Acid; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Humans; Kaplan-Meier Estimate; Keratins; Melanoma; Mutation; Prognosis; Protein Interaction Maps; RNA, Messenger; Signal Transduction; Skin Neoplasms

Deviations from the classic melanocytic immunophenotype in melanoma can present a diagnostic challenge. PAX8 and PAX2 are common markers for renal or Müllerian differentiation. While most PAX8+ or PAX2+ carcinomas are seldom confused with melanoma, some cases may show a more ambiguous immunophenotype, especially when MiTF family altered renal cell carcinoma (MiTF-RCC) is in the differential diagnosis. Neither PAX8 nor PAX2 expression has been reported in melanoma to date. We aimed to better characterize PAX8, PAX2, and cytokeratin immunoreactivity in a large series of melanomas.. Tissue microarrays consisting of 263 melanomas were immunostained for PAX8, PAX2, and cytokeratin and graded by an h-score.. PAX8 expression was seen in 7.9% of melanomas and was significantly associated with spindle cytomorphology. PAX2 was positive in one (0.4%) melanoma. Cytokeratin positivity was seen in three (1.2%) cases and was associated with metastases.. PAX8 is expressed in a subset of melanomas and may be strong/extensive. As PAX8 positivity does not exclude a diagnosis of melanoma, it should be used in conjunction with other immunohistochemical markers, such as cytokeratin and PAX2, when melanoma, MiTF-RCC, and other PAX8+ tumors are in the differential diagnosis.

Topics: Biomarkers, Tumor; Carcinoma; Diagnosis, Differential; Humans; Immunohistochemistry; Keratins; Melanoma; Melanoma, Cutaneous Malignant; PAX2 Transcription Factor; PAX8 Transcription Factor; Skin Neoplasms

Seborrheic keratoses (SKs) are harmless pigmented skin lesions (PSLs) that may be confused clinically not only with other benign conditions but also with cutaneous melanoma (CM). As SKs are one of the most common neoplasms in adults, the importance of their correct diagnosis is high. Misclassifying SK as malignant is not rare and leads to a high number of unnecessary biopsies. On the other hand, misdiagnosing CM as SK may have a large impact on prognosis or therapy.. In the non-invasive technique of dermatofluoroscopy, the fluorophores in melanocytes and keratinocytes are excited in vivo with nanosecond laser pulses and the resulting spectrally resolved, melanin-dominated fluorescence signals are used to differentiate between pigmented benign lesions and CM.. In this single-center, non-interventional study, 33 PSLs of 20 patients were scanned with dermatofluoroscopy in vivo. For all included cases, dermatofluoroscopic signals were compared to pathology classification.. The characteristic spectral features of SK were identified, where the signals are dominated by keratin, NAD(P)H, and melanin. The fluorescence spectra of SKs differed substantially from those of CM: a characteristic spectrum of SK has been identified in 27 of 28 SKs.. The high-accuracy differential diagnosis between CM and SK is possible with dermatofluoroscopy.

Topics: Adult; Diagnosis, Differential; Humans; Keratins; Keratosis, Seborrheic; Melanins; Melanoma; NAD; Skin Neoplasms

Pigmented extramammary Paget disease (PEMPD) is a rare intraepithelial carcinoma which can clinically resemble other pigmented neoplasms. Similarities to melanoma on dermoscopy, histopathology, and reflectance confocal microscopy (RCM) increase the risk of misdiagnosis and, consequently, mismanagement. Here, we describe a case of a 67-year-old African American woman with a large, pigmented axillary patch that exhibited features of melanoma on RCM, guiding the clinician to perform an excisional biopsy. While traditional histopathology resembled melanoma, immunohistochemistry staining was performed and revealed PEMPD. We highlight an uncommon clinical presentation of PEMPD disease and identify morphologic mimickers of melanoma on RCM-as well as differentiating features.

Topics: Aged; Axilla; Biopsy; Black or African American; Dermoscopy; Diagnosis, Differential; Diagnostic Errors; Female; Humans; Hyperpigmentation; Hyperplasia; Immunohistochemistry; Keratins; Melanocytes; Melanoma; Microscopy, Confocal; Paget Disease, Extramammary

Neoplasms consisting of different cell lineages within a single skin specimen are rare, yet well documented in the literature. However, to date, there appears to be no report of invasive melanoma arising directly from the passenger melanocytes of a basal cell carcinoma (BCC). We present a case of a 91-year-old male with a suspicious lesion on the ear. Histopathology and immunohistochemical staining revealed BCC closely intertwined with invasive melanoma that exhibited foci of chondroid differentiation. The melanoma appeared to arise from the benign-appearing passenger melanocytes of the BCC and lacked connection to the overlying epidermis or an in situ component. Multiple dermatopathologists reviewed the case and agreed that the most likely explanation for the histopathologic findings was that the invasive melanoma arose from the passenger melanocytes within the BCC.

Topics: Aged, 80 and over; Carcinoma, Basal Cell; Ear Neoplasms; Humans; Immunohistochemistry; Keratins; Male; Melanocytes; Melanoma; Melanoma, Cutaneous Malignant; Neoplasm Invasiveness; Neoplasms, Multiple Primary; S100 Proteins; Skin Neoplasms; SOXE Transcription Factors; Treatment Refusal

Desmoplastic melanoma (DM) is an uncommon variant of malignant melanoma (MM), histologically characterized by a mainly dermal proliferation of spindled cells within a desmoplastic stroma. Normally, involvement of deeper tissues by DM is the result of direct extension down from the overlying dermis. MM is widely known to harbor a striking potential for morphological and phenotypic variability; among MM morphological variants, pseudoglandular MM is characterized by extensive discohesion within cords and nests of malignant cells and ensuing formation of so-called pseudolumina, thus mimicking adenocarcinoma. We present an exceptional case of DM characterized by intrafascial origin, partly pseudoglandular differentiation, and aberrant experession of cytokeratins in the pseudoglandular component; genetic data from next-generation sequencing supported the final diagnosis of DM, as well as the ontogenetic identity of the pseudoglandular component. Prior to this report, pseudoglandular features had never been described in DM. Additionally, our case is unusual because of the deep origin of the tumor, arising below the subcutaneous fat of the scalp, as well as the aberrant experession of cytokeratins in the pseudoglandular component, thus posing a challenging differential diagnosis with several soft tissue tumors.

Topics: Aged; Biomarkers, Tumor; Cell Differentiation; Diagnosis, Differential; Head and Neck Neoplasms; Humans; Keratins; Male; Melanoma; Predictive Value of Tests; Scalp; Skin Neoplasms

Melanoma is one of the great mimickers in pathology because it has diverse morphologies and can be mistaken for carcinoma or sarcoma. In most cases, immunochemistry is helpful in supporting the diagnosis and excluding other differentials. However, metastatic melanoma may lose immunohistochemical melanocytic markers and express nonmelanocytic lineage markers, which often poses a diagnostic dilemma and may be misdiagnosed as a poorly differentiated carcinoma or sarcoma. We report the case of a 52-year-old woman who had a history of recurrent melanoma on her right shoulder with axillary lymph node metastasis (BRAF V600K-mutated melanoma) and right-side breast-invasive ductal carcinoma (stage pT1b N0sn). One year later, she presented with a left-sided chest wall mass and enlarging left axillary lymph nodes. Needle core biopsies were obtained from both lesions, and histologic examination showed a poorly differentiated tumor with pleomorphic/anaplastic morphology and necrosis. The tumor cells were strongly immunoreactive for GATA-3 without expression of melanocytic markers (S100, Melan A, HMB45, SOX10, MITF, and tyrosinase). The history of melanoma prompted molecular analysis, and the lesion was found to harbor the BRAF V600K mutation, consistent with metastatic dedifferentiated melanoma. Recognition of metastatic dedifferentiated melanoma is important to avoid misdiagnosis of carcinoma, especially in patients with a previous history of carcinoma.

Topics: Breast Neoplasms; Carcinoma, Ductal, Breast; Cell Dedifferentiation; Female; GATA3 Transcription Factor; Humans; Keratins; Lymphatic Metastasis; Melanoma; Middle Aged; Neoplasms, Second Primary; Skin Neoplasms

We report the case of a 94-year-old man with a rapidly growing nodule on the preauricular area, which on histology showed a poorly differentiated spindle cell tumor with negative p63 and p40 antibody immunostains, negative high- and low-molecular-weight cytokeratins albeit for a focal expression of cytokeratin AE1/AE3. Spindle cell melanoma, angiosarcoma, and leiomyosarcoma were excluded. We explore the diagnostic approach to this challenging conundrum. Certain authors have suggested that sarcomatoid carcinoma and atypical fibroxanthoma (AFX) may lie within a spectrum of "sarcoma-like tumors of the head and neck" and that they may all run a similarly indolent clinical course. However, AFX appears to remain a diagnosis of exclusion, and expert consensus is that by definition AFX cannot express any cytokeratin antigens.

Topics: Aged, 80 and over; Biomarkers, Tumor; Carcinoma; Diagnosis, Differential; Face; Hemangiosarcoma; Humans; Keratins; Leiomyosarcoma; Male; Melanoma; Mohs Surgery; Skin; Skin Neoplasms

The characterization of poorly differentiated neoplasms in fine-needle aspiration (FNA) and small biopsy specimens usually requires immunohistochemistry (IHC) with a panel of markers. Because of an increasing need to preserve limited diagnostic material for tumor genotyping and a mounting demand for cost containment, the authors investigated the usefulness of dual-color IHC with antibodies directed against broad-spectrum keratins and SOX10, a neuroectodermal transcription factor consistently expressed in melanoma, in the workup of epithelioid malignant neoplasms.. A total of 107 cases of FNA cell blocks (49 cases) and small biopsies (58 cases) were selected, including 34 melanomas, 31 epithelioid/pleomorphic sarcomas, and 42 carcinomas. IHC was performed on all specimens using a peroxidase-based brown chromogen for SOX10 and an alkaline phosphatase-based red chromogen for keratins AE1/AE3. The presence or absence of staining in lesional cells was scored.. The majority of tumors demonstrated 1 of 3 distinct patterns: 1) malignant melanomas with nuclear SOX10 (sensitivity of 94% and specificity of 95%); 2) epithelioid/pleomorphic sarcomas negative for both SOX10 and AE1/AE3 (sensitivity of 84% and specificity of 88%); and 3) carcinomas with cytoplasmic AE1/AE3 (sensitivity of 76% and specificity of 98%). In addition, a fourth pattern with cytoplasmic AE1/AE3 and nuclear SOX10 was observed in a subset of carcinomas, most notably triple-negative breast cancers.. SOX10/keratin dual-color IHC appears to be an effective, sensitive, and specific test to distinguish between melanoma, sarcoma, and carcinoma. This approach can identify melanoma, prioritize additional studies, and limit the number of markers needed to workup an epithelioid malignant neoplasm, thereby potentially reducing costs and preserving valuable tissue for ancillary studies with which to guide therapy. Cancer Cytopathol 2018;126:179-89. © 2018 American Cancer Society.

Topics: Biopsy, Fine-Needle; Cell Differentiation; Color; Humans; Immunohistochemistry; Keratins; Limit of Detection; Melanoma; Skin Neoplasms; SOXE Transcription Factors

Topics: Adult; Biomarkers, Tumor; Calmodulin-Binding Proteins; Diagnosis, Differential; Gastrointestinal Neoplasms; Gastrointestinal Stromal Tumors; High-Throughput Nucleotide Sequencing; Humans; Immunohistochemistry; In Situ Hybridization, Fluorescence; Keratins; Male; MART-1 Antigen; Melanoma; Middle Aged; Neoplasm Recurrence, Local; Neuroectodermal Tumors; RNA-Binding Proteins; S100 Proteins; Sarcoma, Ewing; SOXE Transcription Factors; Synaptophysin

To investigate the immunohistochemical expression (IHCE) of selected keratins in primary cutaneous and mucosal melanoma (pM), and metastatic melanoma (metsM) of the head and neck and to compare their expression to a group of undifferentiated/poorly differentiated tumors of the same anatomic region.. IHCE of K6, K7, K8, K14, K16, K18, and K19 were studied in 29 melanomas and 70 cases of non-melanoma tumors of the same anatomic region (neuroendocrine carcinoma, neuroblastoma, olfactory neuroblastoma, sinonasal undifferentiated carcinoma, undifferentiated nasopharyngeal carcinoma, anaplastic large cell lymphoma, poorly differentiated squamous cell carcinoma (PDSCC), and Ewing sarcoma). MNF-116 pancytokeratin was investigated in melanoma.. All studied keratins, except K6, were expressed in melanoma. IHCE of MNF-116, K8, and K18 was higher in metsM compared with pM. K14 and K16 expression was highest in PDSCC.. metsM expresses keratins more than pM, specifically K8, K18, and MNF-116. Keratin positivity in an undifferentiated or poorly differentiated neoplasm does not necessarily exclude the diagnosis of melanoma.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Female; Head and Neck Neoplasms; Humans; Immunoenzyme Techniques; Keratins; Male; Melanoma; Middle Aged

Topics: Adult; Aged; Aged, 80 and over; Cell Proliferation; Cells, Cultured; Consensus; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Keratinocytes; Keratins; Male; Melanocytes; Melanoma; Microphthalmia-Associated Transcription Factor; Microphthalmos; Middle Aged; Neurogenesis; Pigmentation; Skin Neoplasms; Young Adult

The workup of a malignant effusion usually requires immunostaining with a panel of markers. Although nuclear Wilms tumor 1 (WT1) expression is widely used to detect tumors of ovarian and mesothelial origin, it is less well known that WT1 is also expressed in the cytoplasm of melanomas and mesenchymal tumors. Because to the authors' knowledge the diagnostic utility of cytoplasmic WT1 expression has not been explored to date, the usefulness of a WT1/AE1/AE3 dual-color immunostain in the workup of malignant effusions was evaluated.. A total of 86 pleural effusions, including 17 metastatic melanomas, 31 metastatic adenocarcinomas, 10 malignant mesotheliomas, 10 lymphoproliferative disorders, 5 metastatic sarcomas, and 13 benign specimens, were immunostained using a peroxidase-based brown chromogen for WT1 and an alkaline phosphatase-based red chromogen for AE1/AE3 on cell block sections.. The majority of malignant effusions stained in 1 of 4 distinctive patterns: 1) all lung and breast adenocarcinomas demonstrated cytoplasmic AE1/AE3 expression without nuclear or cytoplasmic WT1 expression; 2) serous carcinomas of Müllerian origin, mesotheliomas, and benign mesothelial cells were positive for cytoplasmic AE1/AE3 as well as nuclear WT1; 3) melanomas, sarcomas, and a subset of plasma cell neoplasms were positive for cytoplasmic expression of WT1 but negative for AE1/AE3; and 4) large B-cell lymphomas and a subset of plasma cell neoplasms were negative for both markers.. A WT1/AE1/AE3 dual-color immunostain can reliably identify malignancy in pleural effusions and group malignant cells into discrete subsets, thereby narrowing the differential diagnosis. This simple double stain can be a cost-effective, first-line test in the workup of patients with malignant effusions.

Topics: Adenocarcinoma; Biomarkers, Tumor; Carcinoma; Coloring Agents; Epithelium; Humans; Immunohistochemistry; Keratins; Lymphoproliferative Disorders; Melanoma; Mesothelioma; Neoplasm Metastasis; Pleural Effusion, Malignant; Sarcoma; WT1 Proteins

Although angiomyolipoma (AML) is a relatively rare entity, it is the most common benign mesenchymal neoplasm of the kidney.. To highlight the clinicopathological characteristics of AML and to assess the role of Human Melanoma Black-45 (HMB-45), Melan-A, smooth muscle actin (SMA), S-100 and cytokeratin in its diagnosis.. The study included 15 cases of AML. Clinical and radiological data were retrieved from the archival files and all cases were subjected to a histopathological evaluation as well as immunohistochemical staining for HMB-45, Melan-A, SMA, S-100, and cytokeratin.. AML was more common in females (female:male = 4:1), the mean age was 53.9 ± 6.45 years. 60% of patients were symptomatic while the remaining 40% were asymptomatic. A statistically significant relationship was found between size of the tumor and the presence of the symptoms (P = 0.02). Patients with tumor size less than 4 cm were asymptomatic, while those with tumor size larger than 4 cm had different symptoms. Thirteen cases were classic AML, while 2 cases were epithelioid AML. Classic AML demonstrated admixture of fatty tissue, thick-walled blood vessels, and smooth muscle, while epithelioid AML was composed mainly of epithelioid cells and contained no fat. HMB-45 was positive in all cases of AML (100%), Melan-A was positive in 13/15 (87%) while SMA was positive in 11/15 (73%) of AML with variable staining intensity. All cases of AML were negative for S-100 and cytokeratin.. AMLs have characteristic clinicopathological and immunohistochemical features and their recognition is crucial for proper diagnosis and treatment.

Topics: Adult; Angiomyolipoma; Carcinoma, Renal Cell; Cohort Studies; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Keratins; Kidney Neoplasms; Male; Melanoma; Middle Aged; Retrospective Studies; S100 Proteins; Tomography, X-Ray Computed

A combined squamomelanocytic tumor is an exceedingly rare occurrence; little is known about its pathogenesis. A definitive diagnosis can only be made via histological examination. We describe herein an 83 year-old man who was discovered to have this combined tumor and recommend the appropriate management for such a lesion.

Topics: Aged, 80 and over; Biomarkers, Tumor; Carcinoma, Squamous Cell; Facial Neoplasms; gp100 Melanoma Antigen; Humans; Keratins; Male; MART-1 Antigen; Melanins; Melanoma; Melanoma-Specific Antigens; Neoplasms, Multiple Primary; S100 Proteins; Skin Neoplasms

Topics: Adult; CD56 Antigen; Chromogranins; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Keratins; Lymph Nodes; Lymphatic Metastasis; Melanoma; S100 Proteins

A limitation of positive selection strategies to enrich for circulating tumor cells (CTCs) is that there might be CTCs with insufficient expression of the surface target marker which may be missed by the procedure. We optimized a method for enrichment, subsequent detection and characterization of CTCs based on depletion of the leukocyte fraction.. The 2-step protocol was developed for processing 20 mL blood and based on red blood cell lysis followed by leukocyte depletion. The remaining material was stained with the epithelial markers EpCAM and cytokeratin (CK) 7/8 or for the melanoma marker HMW-MAA/MCSP. CTCs were detected by flow cytometry. CTCs enriched from blood of patients with carcinoma were defined as EpCAM+CK+CD45-. CTCs enriched from blood of patients with melanoma were defined as MCSP+CD45-. One-hundred-sixteen consecutive blood samples from 70 patients with metastatic carcinomas (n = 48) or metastatic melanoma (n = 22) were analyzed.. CTCs were detected in 47 of 84 blood samples (56%) drawn from carcinoma patients, and in 17 of 32 samples (53%) from melanoma patients. CD45-EpCAM-CK+ was detected in pleural effusion specimens, as well as in peripheral blood samples of patients with NSCLC. EpCAM-CK+ cells have been successfully cultured and passaged longer than six months suggesting their neoplastic origin. This was confirmed by CGH. By defining CTCs in carcinoma patients as CD45-CK+ and/or EpCAM+, the detection rate increased to 73% (61/84).. Enriching CTCs using CD45 depletion allowed for detection of epithelial cancer cells not displaying the classical phenotype. This potentially leads to a more accurate estimation of the number of CTCs. If detection of CTCs without a classical epithelial phenotype has clinical relevance need to be determined.

Topics: Antigens, Neoplasm; Ascites; Biomarkers, Tumor; Calibration; Cell Adhesion Molecules; Cell Line, Tumor; Epithelial Cell Adhesion Molecule; Humans; Immunomagnetic Separation; Keratins; Leukocyte Common Antigens; Lymphocyte Depletion; Melanoma; Microspheres; Nanoparticles; Neoplasms; Neoplastic Cells, Circulating; Pleural Effusion

Topics: Abdominal Neoplasms; Adolescent; Diagnosis, Differential; Fibroblasts; Groin; Histiocytoma, Malignant Fibrous; Humans; Keratins; Lymph Nodes; Lymphoma; Male; Melanoma; Vimentin

In recent years, Mohs micrographic surgery (MMS) has become a widely utilized method of removal for a variety of cutaneous neoplasms. Certain clinical scenarios, however, make it difficult to visualize residual tumor cells, potentially decreasing the efficacy of the Mohs procedure. Immunohistochemical (IHC) stains are now available and are being utilized to delineate cells of interest intraoperatively when routinely stained slides are equivocal. While useful, IHC stains have not gained wide acceptance as an adjunct to MMS, particularly due to increased processing time, cost and workload required. There have been multiple recent advances, however, in the utilization of IHC stains in MMS. In this article, the authors discuss recent advances in IHC stains used in MMS for the treatment of melanoma as well as nonmelanoma skin cancers, potentially making their routine use in select cases more feasible.

Topics: Humans; Immunohistochemistry; Keratins; Melanoma; Mohs Surgery; Skin Neoplasms

Topics: Adult; Diagnosis, Differential; Follow-Up Studies; Humans; Infant; Keratins; Male; Mandibular Neoplasms; Melanoma; Neuroblastoma; Neuroectodermal Tumor, Melanotic; Rhabdomyosarcoma, Embryonal; Synaptophysin

Occasional reports indicated cytokeratin (CK) protein expression (mainly by immunohistochemistry) in malignant melanoma (MM) and suggested an association with unfavorable clinical parameters. However, the mRNA expression of CK and its clinicopathologic significance in MM has not been specifically evaluated. We investigated the mRNA and protein expression of nine CKs in melanoma cell lines and tissues, in particular the prognostic significance of CK18 mRNA expression. Reverse transcription (RT)-PCR (CK6-10, 14 and 18-20), in-situ hybridization (ISH) (CK18), and western blotting (CK18 and pan-cytokeratin AE1/AE3) were performed on MM cell lines A375, A875, M14, and SK-MEL-1. Eighty MM tissue samples were analyzed by ISH and immunohistochemistry for CK18 expression. The mRNA of CK6-8, 10, 14, 18, and 19 (but not CK9 and 20) was detected in one to four of the melanoma cell lines by RT-PCR. CK18 was detected in all four cell lines by RT-PCR, ISH, and western blotting. CK18 mRNA ISH was positive in three of 30 (10.0%), 10 of 25 (40.0%), and 12 of 25 (48.0%) of primary cutaneous, primary mucosal, and metastatic melanomas, respectively (overall positivity: 25 of 80, 31.3%). CK18 immunostaining was only observed focally in eight of 80 (10.0%) of MM tissue samples, and AE1/AE3 immunostaining was altogether negative. Significantly, CK18 mRNA ISH positivity (but not protein immunohistochemistry) was associated with poorer prognosis by both univariate analysis (P<0.001) and multivariate analysis (relative risk=5.430, 95% confidence interval 2.246-13.128, P<0.001). CK18 mRNA could be identified in one-third of melanoma tissue samples and is an adverse prognostic factor. ISH is superior to immunohistochemistry for analyzing CK18 expression in MM.

Topics: Blotting, Western; Bone Neoplasms; Brain Neoplasms; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Humans; Immunoenzyme Techniques; In Situ Hybridization; Kaplan-Meier Estimate; Keratin-18; Keratins; Lymphatic Metastasis; Melanoma; Neoplasm Proteins; Prognosis; Proportional Hazards Models; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm; Skin Neoplasms

Atypical fibroxanthoma (AFX) (dermal pleomorphic sarcoma) remains a somewhat controversial entity. Some authors have averred that AFX is a fiction, suggesting that such lesions merely represent misclassified examples of spindled squamous cell carcinoma. In addition, the immunoperoxidase confirmation of AFX has been less than straightforward and has historically been approached as a diagnosis of exclusion because of the lack of sensitivity and specificity of available "positive" reagents. Procollagen 1 (PC1) and CD10 represent recently developed immunoperoxidase reagents that have been forwarded as useful in this setting, and we sought to characterize our experience, both to confirm the utility of these antibodies and to compare them. Our investigation included 3 separate data sets. Group 1 consisted of a retrospective review of 98 consecutive cases in which PC1 was used in the evaluation of dermatopathology specimens in routine practice during a 13-month interval. Group 2 consisted of a direct comparison of 11 AFX, 11 dermatofibroma (DF), and 7 epithelioid dermatofibroma (EDF) using the CD10 reagent on cases identified by database search. Group 3 consisted of a retrospective review of 47 cases in which CD10 was used in routine practice during a 10-month interval. Group 1 included 47 AFX, 13 carcinomas, and 6 melanomas. PC1 expression was observed in 45 of 47 AFX (96%), with a strong reaction in 78% of cases. Among a comparison group of carcinomas, 13 of 13 displayed strong keratin immunopositivity and 11 of 13 (85%) lacked PC1 expression whereas 2 showed focal weak labeling. Six of six melanomas exhibited avid S100 expression and none labeled with PC1. In group 2, strong CD10 immunoreactivity was present in 11 of 11 AFX. Similarly, 11 of 11 DFs were also positive. In contrast, 6 of 7 cases of EDF lacked CD10 expression. Group 3 included 38 AFX and 9 miscellaneous spindle cell proliferations. Of the 38 AFX, 37 (97%) labeled with CD10 and in 34 (92%) the reaction was strong. PC1 immunostaining was also completed in 34 of 38 AFX from group 3 and 27 (79%) cases showed positive labeling. Our results confirm that both PC1 and CD10 can be used as positive markers of AFX. We believe that CD10 and PC1 immunostaining can be used as a useful adjunct to supplement the diagnosis of AFX, within the context of an immunoperoxidase panel. Not surprisingly, CD10 expression is also common in DF, a benign analog of AFX, with the exception of its epithelioid variant. In direc

Topics: Adult; Aged; Aged, 80 and over; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Collagen Type I; Diagnosis, Differential; Epithelioid Cells; Female; Histiocytoma, Benign Fibrous; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Middle Aged; Neprilysin; Predictive Value of Tests; Procollagen; Reproducibility of Results; Retrospective Studies; S100 Proteins; Sarcoma; Skin Neoplasms; Xanthomatosis

Topics: Aged; Biomarkers, Tumor; Biopsy, Fine-Needle; Female; Goiter; Humans; Immunohistochemistry; Keratins; Lymph Nodes; Lymphatic Metastasis; Melanoma

Topics: Diagnosis, Differential; Humans; Immunophenotyping; Keratins; Lymphatic Metastasis; Melanoma; Middle Aged; Mouth Neoplasms; Prognosis; Submandibular Gland Neoplasms

Endothelial progenitor cells (EPCs) have been shown to contribute to experimentally induced choroidal neovascularisation (CNV) in animal models. The recruitment pathway for EPCs is dependent on the chemokine stromal cell derived factor 1-alpha (SDF) and its receptor CXCR4 on the progenitor cell. We examined 23 specimens of CNV occurring secondary to a variety of aetiologies (10 secondary to age-related macular degeneration (AMD), 4 inflammatory, 4 idiopathic and 5 melanoma-associated) for the presence and distribution of SDF and CXCR4 in order to determine if this pathway may play a role in neovascularisation. Specimens were examined by immunohistochemistry using a panel of antibodies against SDF, CXCR4, vascular endothelial growth factor receptor 2 (VEGFR-2), CD34 (endothelial cells), CD68 (macrophages) and cytokeratins (retinal pigment epithelium; RPE). SDF was detected in 2 cases of CNV in AMD, 1 inflammatory CNV, 3 idiopathic CNVs and in 3 cases of CNV associated with melanoma. A significant association was found between SDF and VEGFR-2 immunostaining in individual membranes (p<0.001). Localisation of SDF immunostaining to the presumed RPE was also significant (p<0.05). CXCR4 immunostaining was widespread in all membranes in keeping with the published work of other investigators. Our study suggests that SDF, which may be produced by the RPE, could play a role in CNV.

Topics: Adult; Aged; Aged, 80 and over; Antigens, CD; Biomarkers; Chemokine CXCL12; Child; Choroid Neoplasms; Choroidal Neovascularization; Choroiditis; Endothelium, Vascular; Female; Humans; Keratins; Macular Degeneration; Male; Melanoma; Mesenchymal Stem Cells; Middle Aged; Receptors, CXCR4; Vascular Endothelial Growth Factor Receptor-2

PEComas arising in somatic soft tissue or skin are rare. To further characterize the clinicopathologic spectrum, we herein report a series of 10 primary cutaneous PEComas. Eight patients were female and 2 patients were male. The age at presentation ranged from 15 to 81 years (median, 52y). None had tuberous sclerosis. Tumor size ranged from 0.7 to 2 cm (median size, 1.5 cm). Eight tumors were located on the limbs and 2 on the back. The tumors involved the dermis and commonly showed infiltration into the subcutaneous fat. Architecturally, a nested, focally trabecular growth pattern with prominent vasculature composed of delicate thin-walled capillaries was observed. Six tumors were composed of epithelioid cells and 4 showed mixed epithelioid and spindle cell morphology. Tumor cells had clear, palely eosinophilic or granular cytoplasm. Multinucleate tumor giant cells were observed in 3 cases. Mitotic activity ranged from 0 to 2 mitoses per 30 high power fields (mean < 1/10 HPF). Pleomorphism or necrosis was absent. All cases showed at least focal positivity for HMB-45. Melan A was positive in 5/7. In cases where HMB-45 was positive in fewer than 5% of tumor cells (5/10), microphthalmia transcription factor was positive in the majority of the tumor cell nuclei. Desmin positivity was observed in 5 and smooth muscle actin in 1 case, respectively. The other muscle markers (caldesmon, calponin) and also pan-keratin and epithelial membrane antigen were negative. Follow-up data were available in 6 cases and ranged between 3 and 108 months (median, 47 mo). None has recurred to date. Primary cutaneous PEComas are rare and thus far apparently benign cutaneous tumors. Accurate recognition of this entity is essential because of potential misdiagnosis as malignant tumors, especially malignant melanoma.

Topics: Actins; Adolescent; Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Biomarkers, Tumor; Calcium-Binding Proteins; Calmodulin-Binding Proteins; Calponins; Dermis; Desmin; Diagnosis, Differential; Female; Giant Cells; Humans; Immunohistochemistry; Keratins; Male; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Microfilament Proteins; Microphthalmia-Associated Transcription Factor; Middle Aged; Mitotic Index; Mucin-1; Neoplasm Invasiveness; Neoplasm Proteins; Skin Neoplasms; Subcutaneous Fat

In general, it has been stated that keratin (K) molecules are glycosylated. During biochemical studies of K subunits, we encountered a glycoprotein that does not judge K subunits.. This study was intended to elucidate how the above glycoprotein co-exists in the K fraction prepared from ISO-HAS (cultured angiosarcoma cell line).. We analyzed and sequenced a remarkable spot, which was shown as a glycoprotein by periodic acid Sciff's (PAS) staining, in the K fraction prepared from ISO-HAS.. The glycoprotein was identified as an N-terminal amino acid sequence covering 10 residues of the spot. A homology search showed that it was identical to that of Hsp47 (matured type), except for one amino acid (seventh amino acid: Val 7 Leu). Similar results were confirmed for four other tumorigenic cell line types. Subsequent PAS staining using the same samples after 2D-PAGE revealed no glycosylated Ks.. No glycosylated Ks were found by PAS staining in the K fraction prepared from four tumorigenic cell line types. During K preparation from cultured human tumor cell lines, Hsps might be associated with K expression in tumor cells.

Topics: Amino Acid Sequence; Amino Acid Substitution; Carcinoma, Squamous Cell; Cell Line, Transformed; Fibrosarcoma; Gene Expression Regulation, Neoplastic; Glycosylation; HeLa Cells; Hemangiosarcoma; HSP47 Heat-Shock Proteins; Humans; Keratinocytes; Keratins; Melanoma; Molecular Sequence Data; Periodic Acid-Schiff Reaction; Skin Neoplasms

Cutaneous spindle cell squamous carcinoma is an uncommon variant of squamous cell carcinoma in which keratinocytes infiltrate the dermis as single cells with elongated nuclei rather than as cohesive nests or islands, and signs of keratinization of conventional squamous cell carcinoma are insubstantial or nonexistent. Spindle cell carcinoma must be distinguished from spindle cell/desmoplastic melanoma, cutaneous leiomyosarcoma, atypical fibroxanthoma (AFX), and scar. In instances when there is no definitive evidence of squamous differentiation, immunohistochemical studies may confer diagnostic discrimination. Twenty-four cases consisting of 12 spindle cell squamous cell carcinomas, 3 AFXs, 3 leiomyosarcomas, 3 desmoplastic melanomas, and 3 scars were evaluated with a battery of immunohistochemical stains, with the specificity and sensitivity of each marker calculated. The immunohistochemical battery consisted of S-100, desmin, CD68, and smooth muscle actin and cytokeratins P KER (keratins predominantly of molecular weight 56 and 69 kd) and low-molecular weight keratin (CAM 5.2), AE1/AE3, p63, and 34 beta E12 (CK903). Spindle cell squamous carcinomas were negative for S-100, CD68, smooth muscle actin, and desmin with the exception of 2 cases with weak staining for smooth muscle actin. 34 beta E12 provided positive results for each spindle cell squamous carcinoma. The other cytokeratin stains were less sensitive for spindle cell squamous carcinoma than 34 beta E12. The final immunohistochemical results were as follows: 34 beta E12 (12/12, 100%), p63 (10/12, 80%), AE1/AE3 (8/12, 67%), low-molecular weight keratin (7/12, 58%), and P KER (4/12, 33%). The 3 AFXs were positive for CD68 and negative for all other stains, whereas the 3 leiomyosarcomas stained positively for desmin and smooth muscle actin and negatively for all other stains. The 3 melanomas stained positively for S-100 and negatively for all other immunohistochemistry. The scars were negative for all stains. In conclusion, our study of 34 beta E12 proved most promising in distinguishing spindle cell squamous carcinoma from the histologic mimickers, AFX, spindle cell melanoma, scar, and leiomyosarcoma.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoma; Carcinoma, Squamous Cell; Cicatrix; Diagnosis, Differential; Female; Histiocytoma, Benign Fibrous; Humans; Immunohistochemistry; Keratinocytes; Keratins; Leiomyosarcoma; Male; Melanoma; Middle Aged; Predictive Value of Tests; Skin Neoplasms

We report a case of exceedingly rare cutaneous neoplasm with histological features of malignancy and uncertain biological potential. The nodular, darkly pigmented facial tumor with central exulceration, size 12 x 10 x 7 mm, of the skin 61-year-old man preauricular left was completely exised. Histologically tumor consists of atypical squamous cells, which express signs of moderate to significant pleomorphism, mitotically active, with foci forming of parakeratotic horn cysts ("pearls"). Characteristically tumor also consists of large number of atypical melanocytes with multifocal pattern, inserted between atypical squamous cells, and which contain large amount of dark brown pigment melanin. Immunohistochemically, squamous cells stain positively with keratin (CK116), melanocytes were stained with S -100 protein, HMB 45, and vimentin, but failed to stain with CK 116. To our knowledge this is the sixth reported case in world literature. The follow-up time of four years no evidence of recurrence or metastasis, similar all reported cases, but it is too short period in estimation to guarantee a benign course. However, it appears that this group of neoplasm may have different prognosis from pure squamous carcinoma or malignant melanoma.

Topics: Carcinoma, Squamous Cell; Cell Differentiation; Facial Neoplasms; Humans; Keratins; Male; Medical Oncology; Melanocytes; Melanoma; Middle Aged; S100 Proteins; Skin Neoplasms; Vimentin

Despite significant advancement in breast cancer therapy, there is a great need for a better understanding of the mechanisms involved in breast carcinogenesis and progression, as well as of the role of epigenetic contributions from stromal cells in mammary tumorigenesis. In this study, we isolated and characterized murine mammary tumor-derived epithelial and myofibroblast cell lines, and investigated the in vitro and in vivo effect of cellular soluble factors produced by the epithelial cell line on tumor cells.. Morphology, immunophenotype, cytogenetics, invasiveness, and tumorigenicity of epithelial (LM-234ep) and myofibroblast (LM-234mf) cell lines isolated from two murine mammary adenocarcinomas with common ancestor were studied. The in vitro effects of LM-234ep conditioned medium on proliferation, cell cycle distribution, and expression of cell cycle proteins, were investigated in LM-234mf cells, mouse melanoma cells (B16-F10), and human cervical adenocarcinoma cells (HeLa). The in vivo anti-tumor activity of LM-234ep conditioned media was evaluated in subcutaneous tumors formed in nude mice by B16-F10 and HeLa cells.. LM-234ep cells were found to be cytokeratin positive and hipertriploid, whereas LM-234mf cells were alpha-smooth muscle actin positive and hypohexaploid. Chromosome aberrations were found in both cases. Only LM-234mf revealed to be invasive in vitro and to secrete active MMP-2, though neither of the cell types were able to produce progressing tumors. LM-234ep-derived factors were able to inhibit the in vitro growth of LM-234mf, B16-F10, and HeLa cells, inducing cell cycle arrest in G0/G1 phase. The administration of LM-234ep conditioned medium inhibited the growth of B16-F10 and HeLa tumors in nude mice.. Our data suggest the existence of epithelial cell variants with tumor suppressive properties within mammary tumors. To our knowledge, this is the first report showing antiproliferative and antineoplastic activities induced by tumor-derived epithelial cells.

Topics: Actins; Adenocarcinoma; Animals; Carcinogenicity Tests; Cell Line, Tumor; Cell Proliferation; Chromosome Aberrations; Culture Media, Conditioned; Epithelial Cells; Female; Gelatinases; Humans; Keratins; Mammary Neoplasms, Experimental; Melanoma; Mice; Mice, Inbred BALB C; Paracrine Communication; Uterine Cervical Neoplasms

The purpose of this study is to evaluate the value of cytokeratin (CK) MNF116 and vimentin in the differential diagnosis of malignant pleural effusions. There were evaluated smears from 30 patients with pleural effusions stained with May-Grünwald Giemsa and Papanicolaou techniques for the routine cytological diagnosis. Additional smears were immunostained with CK MNF116 and vimentin using LSAB2 technique. Two independent observers evaluated all smears. Smears were classified first by cytological examination in seven cases (23.33%) as benign, and in 23 cases (76.67%) as malignant pleural effusions. Mesothelial cells expressed CK MNF116 in 96.67% (29/30) of cases and vimentin in 33.33% (10/30) of cases. Malignant cells expressed CK MNF116 in 52.17% (12/23) of cases and vimentin in 30.43% (7/23) of cases. The pattern of immunostaining was diffuse cytoplasmic. In conclusion, CK MNF116 and vimentin may be used as a part of the panel of antibodies for differential diagnosis of malignant pleural effusions with primary unknown.

Topics: Adenocarcinoma; Antibodies; Carcinoma, Small Cell; Diagnosis, Differential; Eosine Yellowish-(YS); Female; Humans; Keratins; Lung Neoplasms; Lymphoma, Large B-Cell, Diffuse; Melanoma; Methylene Blue; Pleural Effusion, Malignant; Pleural Neoplasms; Vimentin

Poorly differentiated, spindle cell malignancies, on sun damaged skin frequently pose a diagnostic challenge for pathologists. The vast majority of these neoplasms ultimately are diagnosed as either atypical fibroxanthoma (AFX), spindle cell melanoma (SCM), and very rarely as spindle cell squamous cell carcinoma (SCSCC), leiomyosarcoma or angiosarcoma. Light microscopic clues may suggest one of these neoplasms, but subtle and overlapping characteristics often render precise diagnosis impossible based on morphological features alone. Immunohistochemistry therefore is necessary to firmly and accurately diagnose the majority of spindle cell malignancies on sun damaged skin. Aim of this case report is to highlight the practical approach to such diagnostic dilemmas.

Topics: Aged, 80 and over; Carcinoma, Squamous Cell; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Keratins; Melanoma; S100 Proteins; Sarcoma; Skin Neoplasms; Vimentin; Xanthomatosis

Gap junctions (GJs) have been shown to play a role in tumor progression including a variety of keratinocyte-derived and non-keratinocyte-derived skin tumors. Here we show that the synthesis of the GJ proteins connexin 26 and connexin 30 (Cx26 and Cx30) is induced in keratinocyte-derived epithelial skin tumors whereas there is either no change or a downregulation of Cx43. Cx26, Cx30, and Cx43 are absent in non-epithelial skin tumors. Further, Cx26 and Cx30 are induced in the epidermis adjacent to malignant melanoma but absent in the epidermis adjacent to benign non-epithelial skin lesions (melanocytic nevi and angioma). The keratinocyte-derived skin tumors are very heterogeneous regarding the Cx26/Cx30 pattern in the epidermis at the periphery of the tumors. We did not observe any difference in the localization of the very similar proteins Cx26 and Cx30 but a variation in intensity of immunoreactivity. As the staining patterns of Cx26 and Cx30 antibodies are not identical to those of CK6, a marker for hyperproliferation, and CK17, a marker for trauma, we discuss that the induction of these gap junctional proteins exceeds a reflection of reactive hyperproliferative or traumatized epidermis. We further discuss the putative roles of these gap junctional proteins in tumor progression.

Topics: Animals; Bowen's Disease; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Connexin 26; Connexin 30; Connexins; Epidermis; Hemangioma; Humans; Keratinocytes; Keratins; Keratosis; Liver; Melanoma; Mice; Mice, Inbred C57BL; Microscopy, Fluorescence; Nevus, Pigmented; Skin Neoplasms; Warts

We observed seborrheic keratoses with many basilar clear cells, creating a microscopic pattern that mimicked a seborrheic keratosis involved by melanoma in situ.. We sought to report a series of these seborrheic keratoses and the immunohistochemical stains used to reach a proper diagnosis.. We reviewed 9 cases of seborrheic keratosis that had a distinctive pattern of basal clear cells with ample cytoplasm. All cases were evaluated by conventional microscopy, and Melan-A, S-100, and high molecular weight keratin 903 immunostains.. The basal clear cells failed to react with Melan-A and S-100 protein antisera. In contrast, these cells labeled with an antikeratin antibody in all cases. In all, 7/9 (78%) showed immunopositivity only at the peripheries of cells, creating a pattern that could be mistaken for a negative stain if not examined at high magnification.. This is a retrospective review of cases limited to a large referral dermatopathology service.. We describe a previously uncharacterized pattern of seborrheic keratosis that can microscopically mimic melanoma in situ. Careful conventional microscopy coupled with a panel of immunostains can allow the proper diagnosis to be reached.

Topics: Aged; Aged, 80 and over; Antibodies; Antigens, Neoplasm; Diagnosis, Differential; Female; Humans; Immune Sera; Immunoenzyme Techniques; Keratins; Keratosis, Seborrheic; Male; MART-1 Antigen; Melanoma; Middle Aged; Neoplasm Proteins; Retrospective Studies; S100 Proteins; Skin Neoplasms; Staining and Labeling

Sarcomatoid carcinomas are rare malignancies which represent poorly differentiated epithelial tumors that may be difficult to recognize as such. While some cases may have obvious epithelial areas, the sarcomatoid areas are poorly distinguishable from true sarcoma at the light microscopic level and, by immunohistochemistry, often show only limited staining for traditional epithelial markers such as cytokeratin or epithelial membrane antigen. This can be particularly problematic for diagnosis on small biopsy specimens. We sought to assess the diagnostic utility of several immunohistochemical markers of epithelial differentiation including p63, MOC-31, and thyroid transcription factor-1 on sarcomatoid carcinomas of the head and neck (19 cases; 'spindle cell carcinomas'), lung (19 cases), and urinary bladder (11 cases). These results were compared to immunohistochemistry for the traditional epithelial markers pan-cytokeratin and epithelial membrane antigen. Staining for p63 showed the greatest diagnostic utility, positive in 63, 50, and 36% of head and neck, lung, and urinary bladder sarcomatoid carcinomas, respectively. p63 stains were positive in many cases where immunohistochemistry was negative for both pan-cytokeratin and epithelial membrane antigen. All three alternative markers were quite specific for epithelial differentiation, each staining less than 10% of the control group of 73 various primary and metastatic sarcomas, melanomas, and benign spindle cell lesions. In conclusion, immunostaining beyond traditional pan-cytokeratin and epithelial membrane antigen may have diagnostic utility in this context.

Topics: Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoma; Diagnosis, Differential; Female; Head and Neck Neoplasms; Humans; Immunohistochemistry; Keratins; Lung Neoplasms; Male; Melanoma; Membrane Glycoproteins; Membrane Proteins; Middle Aged; Mucin-1; Nuclear Proteins; Sarcoma; Sensitivity and Specificity; Thyroid Nuclear Factor 1; Transcription Factors; Urinary Bladder Neoplasms

We discuss here five cases of epithelioid sarcoma (ES) with final diagnosis established after reexamination of initial findings. Problems with differential diagnosis of these neoplasms arise since their microscopic picture may simulate several other pathological conditions such as non-neoplastic granulomatous reactions, squamous cell carcinomas and adenocarcinomas, melanomas and soft tissue sarcomas with epithelioid component. Final ES diagnosis requires presence of cytokeratin, EMA and vimentin in neoplastic cells, as confirmed by immunohistochemical reactions. Differential diagnosis is also helped by concurrent cytology assessment that allows recognizing more easily such characteristic features as presence of plasmacytoid or spindle-shaped cells.

Topics: Adenocarcinoma; Adult; Aged; Antigens, CD34; Carcinoma, Squamous Cell; Diagnosis, Differential; Female; Granuloma; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Middle Aged; Mucin-1; S100 Proteins; Sarcoma; Soft Tissue Neoplasms; Vimentin

Basal keratinocytes in the epidermis and hair follicle are biologically heterogeneous but must include a stable subpopulation of epidermal stem cells. In animal models these can be identified by their retention of radioactive label due to their slow cycle (label-retaining cells) but human studies largely depend on in vitro characterization of colony forming efficiency and clonogenicity. Differential integrin expression has been used to detect cells of increased proliferative potential but further stem cell markers are urgently required for in vivo and in vitro characterization. Using LHM2, a monoclonal antibody reacting with a high molecular weight melanoma-associated proteoglycan core protein, a subset of basal keratinocytes in both the interfollicular epidermis and the hair follicle has been identified. Coexpression of melanoma-associated chondroitin sulfate proteoglycan with keratins 15 and 19 as well as beta 1 and alpha 6 integrins has been examined in adult and fetal human skin from hair bearing, nonhair bearing, and palmoplantar regions. Although melanoma-associated chondroitin sulfate proteoglycan coexpression with a subset of beta 1 integrin bright basal keratinocytes within the epidermis suggests that melanoma-associated chondroitin sulfate proteoglycan colocalizes with epidermal stem cells, melanoma-associated chondroitin sulfate proteoglycan expression within the hair follicle was more complex and multiple subpopulations of basal outer root sheath keratinocytes are described. These data suggest that epithelial compartmentalization of the outer root sheath is more complex than interfollicular epidermis and further supports the hypothesis that more than one hair follicle stem cell compartment may exist.

Topics: Animals; Cell Compartmentation; Chondroitin Sulfate Proteoglycans; Epidermal Cells; Epidermis; Gene Expression; Hair Follicle; Humans; Integrin alpha6; Integrin beta1; Keratin-15; Keratinocytes; Keratins; Melanoma; Membrane Proteins; Mice; Skin Neoplasms; Stem Cells

This study established the utility of cross-species application of the cDNA microarray technique for investigating differential gene expression. Using both total RNA and mRNA samples recovered from two opossum cell lines derived from UVB-induced melanoma, we analyzed expression of ca. 4400 genes on the human DermArray DNA microarrays. The signals generated on the DermArrays were clear, strong, and reproducible. A cDNA dot blot consisting of differentially expressed genes representative of different functional clusters was used to validate the DermArray results. We also cloned a Monodelphis gene, keratin 18 (KRT18), and characterized its expression patterns in tumor samples of different progression stages. Up-regulated expression was observed for the KRT18 gene in advanced melanomas, a finding consistent with the DermArray analysis. These results provide evidence that cross-species application of cDNA microarrays is a useful strategy for investigating gene expression patterns in animal models for which species-specific cDNA microarrays are not available.

Topics: Amino Acid Sequence; Animals; Base Sequence; Cloning, Molecular; DNA, Complementary; Down-Regulation; Gene Expression Regulation, Neoplastic; Humans; Keratins; Melanoma; Molecular Sequence Data; Neoplasm Metastasis; Neoplasms, Radiation-Induced; Oligonucleotide Array Sequence Analysis; Opossums; Reverse Transcriptase Polymerase Chain Reaction; RNA; Species Specificity; Ultraviolet Rays; Up-Regulation

Our case of pigmented mammary Paget's disease simulated melanoma clinically and dermoscopically. Histologically, the lesion was characterized by microscopic features similar to those seen in malignant melanoma and, to a lesser extent, in Bowen's disease (intra-epidermal squamous cell carcinoma). Immunohistochemical studies demonstrated that the tumor cells were positive for keratins (Cam 5.2+MNF 116) and AE1-AE3 and negative for HMB-45 and S-100 proteins. In conclusion clinical and dermoscopic examination cannot reliably distinguish melanoma from epithelial pre-neoplastic or neoplastic disease, therefore the differentiation of pigmented Paget's disease from superficial spreading of melanoma and Bowen's disease is based on histopathologic integrated with immunohistochemical criteria.

Topics: Adult; Breast Neoplasms; Diagnosis, Differential; Female; Humans; Keratins; Melanoma; Paget's Disease, Mammary; Skin Neoplasms

Topics: Antigens, Neoplasm; Biomarkers; Carcinoembryonic Antigen; Epithelium; Humans; Immunohistochemistry; Keratins; Melanoma; Melanoma-Specific Antigens; Nasal Mucosa; Neoplasm Proteins; Paranasal Sinus Neoplasms; S100 Proteins; Skin Neoplasms

Adenomas of the non-pigmented epithelium of the ciliary body are rare neoplasms and most of the studies are in the form of case reports. There are only 27 documented cases of acquired neoplasm of the non-pigmented ciliary epithelium (NPCE) reported in the English literature. In most reports, there was a clinical suspicion of melanoma and the diagnosis of NPCE adenoma was made on histopathological evaluation of the resected tissue. The entity has not been reported in the Pakistani population to date. This report describes a case of ciliary body adenoma of NPCE in a 27 year old Pakistani man. The histological and immunohistochemical profiles were typical of the adenomas described in the literature.

Topics: Adenoma; Adult; Ciliary Body; Coloring Agents; Diagnosis, Differential; Eye Neoplasms; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Pakistan; S100 Proteins; Vimentin

The current report describes a malignant melanoma in the dermis of a 13-year-old bay Thoroughbred mare. Microscopic examination revealed that tumor cells were arranged in cords and packets within an abundant collagenous stroma containing scattered myxomatous foci. Tumor cells stained positively for S-100, neuron-specific enolase, and vimentin and some contained melanin granules. Some clusters of tumor cells were also positive for pancytokeratin. Expression of epithelial cell markers has been described in small numbers of human melanomas but has not been reported previously in equine melanomas.

Topics: Animals; Female; Gene Expression Regulation, Neoplastic; Horse Diseases; Horses; Keratins; Melanoma

Though acral lentiginous melanoma (ALM) is a major type of malignant melanoma, no immunohistochemical study on this type of melanoma has been reported.. The purpose of this study is to analysis the immunohistochemical findings of ALM using routinely used immune markers.. An immunohistochemical study was performed on paraffin sections of 20 ALMs using S-100 protein, HMB-45, MART-1, vimentin, epithelial membrane antigen (EMA) and CAM 5.2.. S-100 protein (95%) was found to be a more sensitive marker than either HMB-45 (80%) or MART-1 (70%) for recognizing ALM. Melanin bleaching was useful for recognizing heavily pigmented ALM using both S-100 protein and HMB-45. The intensity of HMB-45 correlated well with the melanin content. However, there was no significant correlation between the intensity of S-100 protein and the melanin content. One and two out of 20 cases stained focally with EMA and CAM5.2, respectively, but these cases stained also with HMB-45 and/or S-100 protein.. S-100 protein and HMB-45 were relatively sensitive markers for recognizing ALM. Despite the occasional positivity for the epithelial markers in ALM, all epithelial marker-positive cases stained also with HMB-45 and/or S-100 protein. Therefore, we recommend that the panel of antibodies used for recognizing ALM should contain at least S-100 protein and HMB-45.

Topics: Aged; Antigens, Neoplasm; Biomarkers; Biomarkers, Tumor; Female; Humans; Immunohistochemistry; Keratins; Male; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Mucin-1; Neoplasm Proteins; S100 Proteins; Skin Neoplasms

To investigate the mode of angiogenesis between highly invasive malignant melanoma and poorly invasive malignant melanoma by immunohistochemistry and periodic acid-Schiff stain (PAS) and to discuss whether the tumor cells in highly invasive malignant melanoma carry vasculogenic mimicry through self-metamorphosis, thus acquiring blood supply to sustain their growth.. Thirty cases of highly invasive malignant melanoma and 30 cases of poorly invasive malignant melanoma were retrieved and reprocessed as tissue microarray for further investigations. The tissue microarray sections were then stained with CD34 and PAS; and the positivity rates were compared.. There was a significant difference between CD34 and PAS staining in highly invasive malignant melanoma (P < 0.01). The difference was not statistically significant in poorly invasive malignant melanoma (P > 0.05).. Vasculogenic mimicry exists in some cases of highly invasive malignant melanoma. It is possible that the tumor cells can acquire blood supply to sustain growth and metastasize via this mechanism.

Topics: Antigens, CD34; Antigens, Neoplasm; Humans; Immunohistochemistry; Keratins; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins; Neovascularization, Pathologic

The immunophenotype of tumor cells and inflammatory infiltrate associated with cutaneous melanocytic lesions (29 melanocytomas, two malignant melanomas, and 23 residual lesions) from 54 adult Iberian and Iberian x Duroc pigs were examined using a panel of nine antibodies. All neoplastic cells were vimentin+, cytokeratin-, and alpha-1-antitrypsin- and the majority were S100+, whereas all pigmented macrophages were vimentin+, cytokeratin-, and S100- and most expressed alpha-1-antitrypsin. Regressing tumors were characterized by zones with low density of neoplastic cells accompanied by heavy infiltration of CD3+ T lymphocytes, whereas zones with high density of neoplastic cells showed very low numbers of CD3+ T lymphocytes. The infiltrate of CD79a+ B cells and IgG, IgM, and IgA plasma cells was low. The majority of lymphocytes of the peri- and intratumoral infiltrate were major histocompatibility complex class II+, but neoplastic cells did not express class II antigen. The 17 residual lesions examined were composed of macrophages containing abundant melanin pigment and low to moderate numbers of CD3+ T lymphocytes. The results of the present study suggest that the local cellular immune response plays a crucial role in the host response that induces regression of cutaneous melanomas and melanocytomas of the Iberian and crossbred Iberian x Duroc pigs.

Topics: alpha 1-Antitrypsin; Animals; Antigens, CD; B-Lymphocytes; CD3 Complex; CD79 Antigens; Histocompatibility Antigens Class II; Immunohistochemistry; Keratins; Melanocytes; Melanoma; Neoplasm Regression, Spontaneous; Plasma Cells; Receptors, Antigen, B-Cell; S100 Proteins; Skin Neoplasms; Swine; Swine Diseases; T-Lymphocytes; Vimentin

The molecular analysis of cancer has benefited tremendously from the sequencing of the human genome integrated with the science of bioinformatics. Microarray analysis technology has the potential to classify tumors based on the differential expression of genes. In the current study, a collaborative, multidisciplinary approach was utilized to study the molecular determinants of human uveal melanoma invasion and metastasis. Uveal melanoma is considered the most common primary intraocular cancer in adults, resulting in the death of approximately 50% of patients affected. Unfortunately, at the time of diagnosis, many patients already harbor microscopic metastases, thus underscoring a critical need to identify prognostic markers indicative of metastatic potential. The investigative strategy consisted of isolating highly invasive vs. poorly invasive uveal melanoma cells from a heterogeneous tumor derived from cells that had metastasized from the eye to the liver. The heterogeneous tissue explant MUM-2 led to the derivation of two clonal cell lines: MUM-2B and MUM-2C. Further morphological and functional analyses revealed that the MUM-2B cells were epithelioid, interconverted (expressing mesenchymal and epithelial phenotypes) highly invasive, and demonstrated vasculogenic mimicry. The MUM-2C cells were spindle-like, expressed only a vimentin mesenchymal phenotype, poorly invasive, and were incapable of vasculogenic mimicry. The molecular analysis of the MUM-2B vs. the MUM-2C clones resulted in the differential expression of 210 known genes. Overall, the molecular signature of the MUM-2B cells resembled that of multiple phenotypes--similar to a pluripotent, embryonic-like genotype. Validation of select genes that were upregulated and down-regulated was conducted by semiquantitative RT-PCR measurement. This study provides a molecular profile that will hopefully lead to the development of new molecular targets for therapeutic intervention and possible diagnostic markers to predict the clinical outcome of patients with uveal melanoma.

Topics: Adult; Down-Regulation; Genotype; Humans; Immunohistochemistry; Keratin-8; Keratins; Male; Melanoma; Microscopy, Fluorescence; Models, Biological; Neoplasm Invasiveness; Neoplasm Metastasis; Oligonucleotide Array Sequence Analysis; Prognosis; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured; Up-Regulation; Uveal Neoplasms; Vimentin

Several reports have documented the coexistence of basal cell carcinoma (BCC) with other lesions, including melanoma. This study was performed to determine whether nests of BCC contain benign melanocytes and Langerhans [corrected] cells. Ten cases of BCC were investigated to determine whether benign melanocytes and Langerhans [corrected] cells populate tumor nests. The BCCs were stained with antibodies to cytokeratin AEI/AE3, S-100, HMB-45, Melan-A, and CD1a proteins. We report that all 10 BCCs were populated by dendritic melanocytes distributed at the periphery (5/10 cases) or evenly throughout tumor nests (5/10 cases). Clusters of melanocytes were not identified in any of the BCCs. A total of 9 of 10 tumors showed staining of dendritic Langerhans cells with CD1a. A total of 8 of 10 tumors stained with cytokeratin AEI/AE3; in 6 of the 8 tumors, the staining was focal. We compared these findings with a single example of a BCC and melanoma in situ (MIS) collision tumor in which the cytokeratin AE1/AE3-positive epithelial nests of BCC were populated by a high density of malignant melanocytes that stained with S-100 and HMB-45. Melanocytes were disposed singly and in clusters of two or more cells within BCC tumor nests. We conclude from this study that BCCs are regularly populated by benign melanocytes and Langerhans [corrected] cells. Furthermore, when BCC is infiltrated with malignant melanocytes of MIS, the melanocyte density is higher and clusters of melanocytes can be observed. The significance of these two findings is unclear, as additional cases of BCC MIS collision tumor need to be studied.

Topics: Antigens, Neoplasm; Biomarkers, Tumor; Carcinoma, Basal Cell; Humans; Immunoenzyme Techniques; Keratins; Langerhans Cells; Melanocytes; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins; Neoplasms, Multiple Primary; S100 Proteins; Skin Neoplasms

Topics: Carcinoembryonic Antigen; Epithelial Cells; Hair Follicle; Humans; Hyperplasia; Keratins; Keratoacanthoma; Melanoma; Mouth Mucosa; Skin; Skin Neoplasms

Mammary Paget's disease unfrequently occurs in males, and may be pigmented in rare instances. Differential diagnosis with malignant melanoma relies on immunohistochemical studies.. A case of Paget's disease of the nipple in a 76 year-old male is reported, clinically mimicking a malignant melanoma because of massive pigmentation. Histologically, large Paget's clear cells were intermingled with numerous melanin-rich dendritic melanocytes. An underlying ductal carcinoma was found. After differential immunohistochemical staining, diagnosis of Paget's disease could be unequivocally substantiated since Paget's cells stained for epithelial markers, c-erbB-2 and hormonal receptors, whereas protein S100 and HMB45 were negative.. Pigmentation in mammary Paget's disease occurs preferentially in males. Pigmentation results from numerous melanocytes with abundant melanin in close contact with Paget's cells. An increased number of melanocytes may also be observed in cutaneous metastatic breast carcinomas. It could result from a chemotactic factor produced by neoplastic cells.

Topics: Aged; Antigens, Neoplasm; Biomarkers, Tumor; Breast Neoplasms, Male; Diagnosis, Differential; Genes, erbB-2; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins; Nipples; Paget's Disease, Mammary; S100 Proteins; Skin Neoplasms

Antibodies recognizing tissue-specific antigens are widely used to identify the histological origin of tumors. Here we tested the fidelity of selected tissue markers on all 167 solid tumor-derived continuous cell lines in the DSMZ cell lines bank. Most lines had an intermediate filament content consistent with the tumor type from which they were derived. Thus, 93% of all carcinoma cell lines expressed keratin filaments. With certain antibodies, some subclassification was possible. For example, the CK7 keratin 7 antibody can differentiate between colon and pancreas-derived carcinoma cell lines. Cell lines derived from non-carcinomas, in general, did not express keratin but were vimentin-positive. Four of 10 glioma/astrocytoma cell lines expressed GFAP, five of six neuroblastoma cell lines expressed neurofilaments, and the TE-671 rhabdomyosarcoma cell line expressed desmin. When other tissue markers were tested, 12/16 melanoma-derived cell lines expressed HMB-45, while PSA, CA125, and thyroglobulin were less useful. These results demonstrate that cell lines retain some but not all markers typical of the original tumor type and identify certain markers useful in characterizing the histological origin of cell lines. Our data question the identity of some cell lines submitted to the bank in the past. The immunoprofiles of 167 solid tumor-derived and 131 hematopoetic cell lines can be found at www.dsmz.de.

Topics: Antibodies, Monoclonal; Antibody Specificity; Antigens, Neoplasm; Antigens, Surface; Blotting, Western; Glial Fibrillary Acidic Protein; Humans; Immunohistochemistry; Keratins; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins; Neurofilament Proteins; Platelet Endothelial Cell Adhesion Molecule-1; Tumor Cells, Cultured; Vimentin

Topics: Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Carcinoma, Squamous Cell; Cholangiocarcinoma; Diagnosis, Differential; Epstein-Barr Virus Infections; Germinoma; Herpesvirus 4, Human; Humans; Immunohistochemistry; Keratins; Lymphoma; Male; Melanoma; Middle Aged; Mucin-1; Skin Neoplasms

Fine-needle aspiration (FNA) of the adrenal is a useful modality for the evaluation of primary and metastatic neoplasms. Until now, however, few reliable markers existed for the positive identification of adrenal cortical cells. Originally studied as a melanoma marker, Melan-A, as detected by the murine monoclonal antibody, A103, has gained recent attention as a marker for steroid-producing cells. Formalin-fixed, paraffin-embedded cell blocks from 24 adrenal FNA specimens were stained for cytokeratins (AE1/AE3) and Melan-A (A103). Seven of 8 cases containing normal, hyperplastic, and neoplastic adrenal cortical cells were positive for A103. Among 16 cases of metastatic carcinoma, tumor cells in 14 samples were positive for cytokeratins but negative for A103. The A103 monoclonal antibody is a sensitive marker for the identification of normal, hyperplastic, and neoplastic adrenal cortical cells in cell blocks of adrenal FNA specimens. With the exception of melanoma, A103 reactivity is restricted to adrenal cortical and other steroid-producing cells. A103 should be used routinely for the evaluation of FNA specimens of adrenal mass lesions.

Topics: Adrenal Cortex; Adrenal Cortex Neoplasms; Animals; Antibodies, Monoclonal; Antigens, Neoplasm; Biomarkers, Tumor; Biopsy, Needle; Cell Nucleus; Humans; Hyperplasia; Immunohistochemistry; Keratins; MART-1 Antigen; Melanoma; Mice; Neoplasm Proteins

Pigmented squamous cell carcinomas have been reported in the oral and ocular mucosae, but rarely in the skin. We present a case of pigmented squamous cell carcinoma of the forehead and review the current English literature. Pigmented squamous cell carcinoma can be confused with pigmented basal cell carcinomas and melanoma, especially those melanomas associated with pseudoepitheliomatous hyperplasia and should be included in the differential diagnosis of atypical pigmented lesions.

Topics: Carcinoma, Squamous Cell; Cell Differentiation; Diagnosis, Differential; Forehead; Humans; Keratins; Male; Melanins; Melanocytes; Melanoma; Melanosis; Middle Aged; Skin Neoplasms

We report a case of cutaneous malignant melanoma associated with extensive pseudoepitheliomatous hyperplasia. Pseudoepitheliomatous hyperplasia may mimic squamous cell carcinoma and may complicate the diagnosis of cutaneous melanoma. This diagnostic pitfall is important to both recognize and be cognizant of, so as to avoid diagnostic errors. The observation of the pseudoepitheliomatous hyperplasia, in this case with an extensive proliferation of eccrine ducts, provides further evidence that cutaneous pseudoepitheliomatous hyperplasia arises within the eccrine apparatus.

Topics: Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoembryonic Antigen; Carcinoma, Squamous Cell; Diagnosis, Differential; Eccrine Glands; Epithelial Cells; Humans; Hyperplasia; Immunoenzyme Techniques; Keratins; Male; Melanoma; Skin; Skin Neoplasms

Topics: Axilla; Biopsy; Breast; Breast Neoplasms; Carcinoma; Epithelial Cells; Female; Humans; Immunohistochemistry; Keratins; Lymph Nodes; Lymphatic Metastasis; Melanoma; Neoplasm Seeding; Skin Neoplasms

Although Merkel cell carcinoma (MCC) exhibits specific clinical and histologic features, differentiation from other cutaneous neoplasms, such as lymphoma, metastatic oat cell carcinoma and malignant melanoma (MM), may sometimes be difficult.. The aim of our study was to immunohistochemically differentiate MCC from MM.. Paraffin sections from 6 cases of primary MCC and 6 cases of primary MM were investigated. For immunostaining, the APAAP method was used.. Neuron-specific enolase was positive in all cases of MCC, as well as in 2 cases of MM. Marked positivity for cytokeratins 18, 20 and chromogranin A was observed in the MCC group, whereas a complete absence of expression of these three markers was noted in the MM group. Immunostaining with HMB45 and NKI/C3 was positive in all cases of MM and negative in all cases of MCC. S-100 protein was positive in all but 1 case of MM. In contrast, only 1 case of MCC reacted with S-100 protein.. Our results underline the role of immunohistochemistry in the diagnosis and differential diagnosis of MCC. In particular, the combination of neuron-specific enolase, cytokeratins 18, 20 and chromogranin A positivity for MCC and HMB45, NKI/C3 and S-100 protein positivity for MM is of great value in the distinction between these two cutaneous neoplasms.

Topics: Antigens, Neoplasm; Carcinoma, Merkel Cell; Chromogranin A; Chromogranins; Diagnosis, Differential; Humans; Immunohistochemistry; Intermediate Filament Proteins; Keratin-20; Keratins; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins; Phosphopyruvate Hydratase; S100 Proteins; Skin Neoplasms

A 47-year-old woman developed metastatic melanoma to the right ovary 14 years after the enucleation of the right eye for a choroidal spindle cell melanoma. An immunohistochemical study was performed on paraffin sections of both primary and metastatic melanoma specimens to identify markers of both aggressive phenotype and metastatic potential with particular attention to the anomalous expression of cytokeratin intermediate filament proteins. Neoplastic cells of both primary and metastatic tumors immunostained positively for S-100, HMB45, MART-1, and vimentin antibodies, but they were negative for cytokeratins 1-19, 8, 18, and 8,18; <10% of neoplastic cells in both the primary and the metastatic melanomas immunostained for Ki-67 proliferating antigen using MIB-1 antibody. We speculate that the indolent behavior of this ovarian metastasis is reflected by the absence of coexpression of cytokeratins 8 and 18 with vimentin. This case supports the practical value of using this panel of antibodies to evaluate the aggressive potential of uveal melanomas.

Topics: Antigens, Neoplasm; Carcinoma; Choroid Neoplasms; Female; Humans; Immunohistochemistry; Immunophenotyping; Intermediate Filament Proteins; Keratins; Ki-67 Antigen; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Ovarian Neoplasms; S100 Proteins; Time Factors; Vimentin

Although rare, renal cell carcinoma (RCC) can metastasize to the bladder. When this occurs, it might complicate diagnosis. Morphologically, RCC can be confused with transitional cell carcinomas (TCCs), especially those exhibiting clear cell features, and also with other bladder tumors, such as paragangliomas and metastatic melanomas. We report seven cases of RCC metastatic to the bladder that occurred in 6 men and 1 woman who were 35 to 69 years old. The most common presenting symptom was the reappearance of hematuria, which developed from 2 to 131 months (mean, 41.3 mo) after the removal of the primary RCC. In all of the patients, the metastatic RCC involved multiple organs; no case had an isolated metastasis to the bladder. The prognosis was poor, and five patients died of disease between 4 and 24 months (mean, 12.8 mo) after diagnosis of the metastasis to the bladder. The remaining two patients were lost to follow-up. All of the tumors were conventional clear or "granular" cell RCCs, with nuclear grades of 2 or 3. In five patients, metastases were confined to the lamina propria, but in two patients, tumors involved the muscularis propria as well. A comparative immunohistochemical study showed that metastatic RCCs were positive for CAM5.2, vimentin, and Leu-M1, and negative for cytokeratin 20, cytokeratin 7, 34betaE12, carcinoembryonic antigen, S-100 protein, HMB45, and chromogranin. Classic and clear cell TCCs were positive for all of the cytokeratins and carcinoembryonic antigen and negative for vimentin. Paragangliomas were positive for chromogranin and showed scattered positivity for the S-100 protein in the sustentacular cells. Metastatic melanomas were positive for S-100 protein and HMB45. The histologic appearance of RCC, particularly the delicate fibrovascular stroma with abundant sinusoidal vessels, is a feature that can be used to recognize the tumor. When there is difficulty diagnosing metastatic RCC, TCC, or other tumors in the bladder, the immunohistochemical findings can assist in the differential diagnosis.

Topics: Adult; Aged; Antigens, Neoplasm; Carcinoembryonic Antigen; Carcinoma, Renal Cell; Carcinoma, Transitional Cell; Chromogranins; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Intermediate Filament Proteins; Keratin-20; Keratin-7; Keratins; Kidney Neoplasms; Lewis X Antigen; Male; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Paraganglioma; S100 Proteins; Urinary Bladder Neoplasms; Vimentin

We report four cases of an unusual cutaneous squamo-melanocytic neoplasm with histological features of malignancy and uncertain biological potential. These tumors developed on the face of middle-aged and older adults. Clinically, a purple-black nodule ranged in size from 3 to 10 mm in maximum diameter. After complete excision, neither recurrence nor metastasis has been observed (mean follow-up time, 3.25 years). Histologically, a discrete dermal nodule surrounded by a fibroblastic stroma was composed of large islands of mitotically active atypical epithelioid cells. The nodule was not connected to the epidermis in three of four cases. Two types of cells were either diffusely admixed or clustered in small groups within the nodule. Small, atypical, epithelioid cells containing finely granular brown pigment, proven to be melanin, constituted the first cell type. The second type consisted of atypical squamoid cells, some with abundant pink cytoplasm, giving rise to squamous pearls. A lentigo maligna was present in one case. The remaining three cases had neither significant intraepidermal melanocytic nor keratinocytic atypia. Immunohistochemical studies indicated that the melanin-containing epithelioid cells expressed S-100 antigens, and the squamoid cells expressed cytokeratins. A small population of tumor cells did not label with either of the antibodies. These four tumors (along with a previously reported, apparently identical tumor arising in the setting of lentigo maligna) represent a unique biphasic dermal neoplasm with histological features of malignancy but, at this time, uncertain biological behavior. Although none have recurred or metastasized, the follow-up time is too short in our estimation to guarantee a benign course. These neoplasms are easily recognized by their characteristic features. Further follow-up evaluations should allow determination of their biologic potential.

Topics: Adult; Aged; Antigens, Neoplasm; Carcinoma, Squamous Cell; Face; Female; Humans; Hutchinson's Melanotic Freckle; Immunohistochemistry; Keratins; Male; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; S100 Proteins; Skin Neoplasms

Topics: Biomarkers, Tumor; Biopsy, Needle; Humans; Keratins; Melanoma

Seborrheic keratosis on the conjunctiva appears to have never been reported in the literature. The authors report here a well-documented case of seborrheic keratosis of conjunctiva clinically simulating a malignant melanoma.. Case report.. A 66-year-old man presented with a juxtalimbal pigmented tumor involving the temporal conjunctiva of his left eye. Because of the rapid enlargement of the mass within a period of 5 months, a clinical diagnosis of malignant melanoma was made. Cytopathologic examinations were performed by impression cytology before the patient underwent a wide en-block excision of the tumor.. Cytologic features were studied by impression cytology with periodic acid-Schiff-Papanicolaou stain. Immunochemical characteristics of tumor cells were studied by immunochemical stain of cytokeratin and HMB-45. Tumor morphology was observed by histopathologic examination.. Impression cytology disclosed basaloid cells intermixing with squamoid cells, and these cells demonstrated positive immunoreactivity to cytokeratin and no reactivity to HMB-45. Histopathologic examination of the tumor specimen established the diagnosis of seborrheic keratosis, and the results of immunohistochemical staining were consistent with those of the impression cytology with immunocytochemical staining.. The authors describe the first case report of conjunctival seborrheic keratosis and present its immunocytochemical and immunohistochemical characteristics. Such a benign lesion can clinically mimic a malignant melanoma.

Topics: Aged; Antigens, Neoplasm; Conjunctival Diseases; Conjunctival Neoplasms; Diagnosis, Differential; Humans; Immunoenzyme Techniques; Keratins; Keratosis, Seborrheic; Male; Melanoma; Melanoma-Specific Antigens; Neoplasm Proteins

Topics: Adult; Antigens, CD; Carcinoma, Signet Ring Cell; Diagnosis, Differential; Female; Humans; Immunoglobulins; Keratins; Liposarcoma; Lymphoma, B-Cell; Mandibular Neoplasms; Melanoma; Organelles; S100 Proteins; Vimentin

Rapid immunostaining of frozen sections within a tolerable time span would be very helpful for intraoperative diagnosis. A protocol was therefore established using the enhanced polymer one-step staining (EPOS) system (Dako) with antibodies against leucocyte common antigen (LCA), cytokeratin (CK), and anti-melanoma (MEL). Best results with reliable and specific immunostaining and a labelling intensity comparable to standard immunostaining protocols were achieved with fixation of samples in 100% acetone for 20 seconds (CK, LCA) or two minutes (MEL), followed by incubation of the primary antibody and development of the chromogen reaction with 3,3'diaminobenzidine (DAB) for three and five minutes at 37 degrees C, respectively. The total procedure takes only 12 minutes, thus enabling rapid immunostaining on intraoperative frozen sections. Apart from its use in tumour classification, this method is especially useful in detecting tumour cells in sentinel lymph nodes.

Topics: Antigens, Neoplasm; Frozen Sections; Humans; Immunohistochemistry; Intraoperative Period; Keratins; Leukocyte Common Antigens; Lymph Nodes; Melanoma; Neoplasms; Staining and Labeling

Human uveal melanoma disseminates initially and preferentially to the liver. This study describes the relationship between the expression of the c-met proto-oncogene (receptor for hepatocyte growth factor/scatter factor (HGF/SF)) in interconverted uveal melanoma cells (co-expressing vimentin and keratin intermediate filaments) and the regulation of their motogenic response to HGF/SF, a key step in local invasion and targeted dissemination to the liver. Expression of c-met in uveal melanoma cell lines correlates with both the appearance of an interconverted phenotype and invasive ability (measured in vitro). Using chemotactic checkerboard analysis, the greatest motogenic response to HGF/SF was achieved by invasive, interconverted, c-met-positive uveal melanoma cells. C-met was observed histologically in a uveal melanoma containing interconverted cells but was absent in a tumor composed of non-interconverted cells (vimentin positive/keratin negative). The c-met ligand, HGF/SF, although not expressed by uveal melanoma cell lines, was localized in tissue sections of primary uveal melanomas and metastatic melanoma to the liver. In the primary tumor, staining for HGF/SF was most intense at the level of the choriocapillaris, a finding that is significant because 1) highly remodeled neovascular loops and networks, which appear in tumors likely to disseminate, can be traced to the choriocapillaris and the draining vortex veins and 2) HGF/SF plays a role in tumor angiogenesis. Foci of metastatic melanoma to the liver stain diffusely for HGF/SF. Regulation of the uveal melanoma interconverted phenotype by HGF/SF may play an important role in the dissemination of this tumor.

Topics: Blotting, Northern; Cell Movement; Hepatocyte Growth Factor; Humans; Immunohistochemistry; Keratins; Liver Neoplasms; Melanoma; Microscopy, Confocal; Models, Biological; Prognosis; Proto-Oncogene Mas; Proto-Oncogene Proteins c-met; Tumor Cells, Cultured; Uveal Neoplasms; Vimentin

We present 14 patients with primary sinonasal melanomas (SM) identified from 1984-1997 in our archives (11/14 lateral nose, 1/14 nasal septum, 2/14 paranasal sinuses; 8M/6F, mean age 67.7 years, range 39-88 years). Survival was poor (median 9 months) with death related to extensive local disease and/or widespread hematogenous metastases. The following histological subtypes were identified in descending order: amelanotic small blue cell, pleomorphic, epithelioid, spindle cell and myxoid. High mitotic rate and vascular invasion, absence of tumor-infiltrating lymphocytes and regression were features shared by all SM. Negative staining of B- and T-cell markers, LCA, neuroendocrine markers such as NSE, chromogranin and synaptophysin, and CK-negativity excluded olfactory neuroblastoma, small cell undifferentiated carcinoma, and lymphoma. S-100 protein was expressed in all SM, but demonstrated variable staining intensity with areas of complete negativity. HMB45 was strongly and uniformly (>80%) expressed in all undifferentiated small blue cell SM. The pigmented SM were predominantly HMB45-negative. The strong HMB45 staining in amelanotic small blue cell SM is explained by the reaction of HMB45 antibody with an oncofetal antigen found in immature melanosomes. In these poorly differentiated amelanotic malignant melanomas, antibody to HMB45 proved to be a superb diagnostic marker. We therefore strongly advocate the inclusion of HMB45 antibody in the panel of antibodies for initial work-up of undifferentiated mucosal neoplasms, since a negative S-100 stain in small biopsy material may result in incorrect classification of these neoplasms.

Topics: Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Female; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Nose Neoplasms; Paranasal Sinus Neoplasms

Immunohistochemistry occasionally is used to determine the lineage of entirely necrotic tumors. However, the sensitivity and specificity of antibodies on necrotic tissue are unknown. To determine the usefulness of immunohistochemistry with necrotic lesions, a series of 24 known tumors consisting of 14 carcinomas, 2 lymphomas, 2 melanomas, and 6 sarcomas (all with extensive necrosis) was examined for reactivity with 6 cytokeratin antibodies, S100, and LCA. Carcinomas stained positively with at least 1 cytokeratin antibody in 78% of the cases. The cytokeratin antibodies with the highest sensitivity were AE1, AE1/3, S903, and PANCK. These antibodies also retained specificity for epithelial differentiation; no reactivity was observed in the 10 necrotic nonepithelial tumors. LCA retained its reactivity with necrotic lymphoma, but S100 reacted with only one third of the necrotic lesions. Unexpectedly, reactivity for LCA and S100 occurred in some necrotic carcinomas. Keratin markers can be used on necrotic tissue to determine epithelial differentiation, but the results obtained with S100 and LCA on necrotic tissue should be interpreted with caution.

Topics: Antibodies; Antibody Specificity; Carcinoma; Diagnosis, Differential; Humans; Immunohistochemistry; Keratins; Leukocyte Common Antigens; Lymphoma; Melanoma; Necrosis; Neoplasm Metastasis; Neoplasms; S100 Proteins; Sarcoma

Malignant melanoma occurring in burn scars is rare and cases of malignant melanoma and squamous cell carcinoma arising in a burn scar are extremely rare. We report a case of malignant melanoma and squamous cell carcinoma arising in one tumour on a stable thermal burn scar on the right leg of a 55-year-old man after a long latent period of about 50 years. The case was unique in that the malignant melanoma and squamous cell carcinoma occurred synchronously next to each other and produced one tumour. Immunohistochemical stainings with keratin, S-100 protein and HMB 45 clearly distinguished the two kinds of atypical tumour cells. Following the total resection of the original tumour, metastasis of malignant melanoma in the inguinal lymph node was found. This case underlines the possibility that another tumour may co-exist even if pathological observation reveals one kind of tumour.

Topics: Antigens, Neoplasm; Antigens, Surface; Burns; Carcinoma, Squamous Cell; Cicatrix; Humans; Immunohistochemistry; Keratins; Leg; Lymphatic Metastasis; Male; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Neoplasms, Multiple Primary; S100 Proteins; Skin Neoplasms

With the exception of two cases, keratin is not expressed in cultured human melanoma cells. Using 2D-PAGE, immunological and electron microscopic analyses, we found keratin subunits in five established cultured cell lines derived from primary, recurrent and metastasized melanomas. The keratin subunits were composed of K1, K5, K10, K14, K15 and K18 in all cell lines examined, together with vimentin. In addition, K8, K16 and K18 expression were demonstrated in recurrent and metastasized cell lines. The results of the present and our previous study [Katagata Y, et al. J Dermatol Sci 1996;13:219-227] indicate that expression of keratin in melanoma cells may be a universal phenomenon. A specific increase in the proportion of K5 among the keratin subunits was suggestive of the nature of melanoma cells. Moreover, we detected two polypeptides that migrated on 2D-PAGE at positions which did not correspond to those of any keratin subunit. The amino acid sequences of these two polypeptides were determined; one was the human ATP synthase alpha-chain but the other did not match any known polypeptide in our homology search.

Topics: Amino Acid Sequence; Antigens, CD; Humans; Keratins; Lung Neoplasms; Lymphatic Metastasis; Melanoma; Membrane Glycoproteins; Molecular Sequence Data; Proton-Translocating ATPases; Recurrence; Sequence Analysis; Tetraspanin 29; Tumor Cells, Cultured

The increased glucose uptake seen in cancer cells correlates with the expression of human erythrocyte glucose transporter (Glut1) protein in certain human malignancies.. Our purpose was to determine Glut1 expression in cutaneous neoplasms.. A polyclonal anti-Glut1 antibody (MYM) and a standard ABC immunoperoxidase technique were used to determine Glut1 expression in invasive squamous cell carcinomas (SCCs), SCC in situ, basal cell carcinomas (BCCs), melanomas, actinic keratoses (AKs), seborrheic keratoses, common acquired nevi, and scars with regenerative epidermal hyperplasia.. All of the cases of SCC in situ, 14 of 15 (93%) of the SCC, and 13 of 15 AKs (87%) showed intense membranous staining for Glut1. Glut1 staining was present in the epidermis of 8 of 15 scars (53%) but was not detected in any BCC, even in areas of focal keratinization and squamous metaplasia. Glut1 reactivity was absent in the melanomas and seborrheic keratoses.. Glut1 expression in a cutaneous lesion strongly suggests a proliferative lesion of the squamous cell type.

Topics: Antibodies; Carcinoma in Situ; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Cell Division; Cicatrix; Dermatitis, Seborrheic; Epidermis; Epithelial Cells; Gene Expression Regulation, Neoplastic; Glucose; Glucose Transporter Type 1; Humans; Hyperplasia; Immunoenzyme Techniques; Keratins; Keratosis; Melanoma; Monosaccharide Transport Proteins; Neoplasm Invasiveness; Nevus; Regeneration; Skin Neoplasms

Intermediate filaments have been used as cell-type-specific markers in differentiation and pathology; however, recent reports have demonstrated the coexpression of vimentin (a mesenchymal marker) and keratins (epithelial markers) in numerous neoplasms, including melanoma, which has been linked to metastatic disease. To test the hypothesis that coexpression of vimentin and keratins by melanoma cells contributes to a more migratory and invasive phenotype, we co-transfected a vimentin-positive human melanoma cell line, A375P (of low invasive ability), with cDNAs for keratins 8 and 18. The resultant stable transfectants expressed vimentin- and keratin-positive intermediate filaments showed a two- to threefold increase in their invasion of basement membrane matrix and migration through gelatin in vitro. These findings were further corroborated by video cinematography. During attachment and spreading on fibronectin, the transfectants containing vimentin and keratins 8 and 18 demonstrated an increase in focal adhesions that stained positive for beta 1 integrin and phosphotyrosine, along with enhanced membrane ruffling and actin stress fiber formation. From these data, we postulate that coexpression of vimentin and keratins results in increased cytoskeletal interactions at focal contacts within extracellular matrices involving integrin cell signaling events, which contributes to a more migratory behavior.

Topics: Cell Adhesion; Cell Movement; Disease Progression; Humans; Keratins; Melanoma; Tumor Cells, Cultured; Vimentin

Topics: Biopsy, Needle; Histocytological Preparation Techniques; Immunoenzyme Techniques; Keratins; Melanoma; Sarcoma

Immunohistochemical detection of certain low to intermediate molecular weight keratins often is impaired in routinely processed specimens due to masking of these antigens by formalin fixation. Despite standard enzymatic digestion, AE1:AE3 and CAM 5.2, two of the most currently utilized antikeratin antibody preparations, either stain weakly or fail to stain basal keratinocytes and tumors composed of basaloid keratinocytes in paraffin sections of formalin-fixed tissue. We present here our experience with the monoclonal antibody MNF116 which detects keratins 5, 6, 8, 17, and 19 (DAKO, Carpinteria, CA). We have studied 232 routinely-processed skin lesions with MNF116 and compared the staining with that of AE1:AE3 mixture or CAM 5.2. In normal skin, the staining achieved with MNF116 was particularly strong on the basal cells of the epidermis and adnexae. MNF116 was positive in all 154 epithelial tumors and negative in all but one (a leiomyosarcoma) of 78 mesenchymal and melanocytic tumors. AE1:AE3 mixture was positive in all but four poorly-differentiated squamous cell carcinomas and it was only weakly positive in most basal cell carcinomas. CAM 5.2 was positive in tumors of the sweat apparatus, Merkel cell carcinomas, metastatic carcinomas, and 5/15 basal cell carcinomas. We consider that, in routinely processed specimens, MNF116 is very useful and convenient for detection of cytokeratin expression in cutaneous lesions, and therefore helpful in the evaluation of tumors with small cells and other poorly differentiated neoplasms of the skin.

Topics: Antibodies, Monoclonal; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Humans; Immunohistochemistry; Keratins; Melanoma; Molecular Weight; Paraffin Embedding; Prospective Studies; Retrospective Studies; Skin Diseases; Skin Neoplasms

An 82-year-old Caucasian man developed an ulcerated mass on the anterior mandibular gingiva. Five years previously he had been treated for a Merkel cell carcinoma (MCC) on his right cheek. Histopathologic examination showed small tumor cells with scanty cytoplasm, suggestive of malignancy. Immunohistochemical studies were performed with the use of nine antibodies. S-100 protein and leukocyte common antigen were helpful in ruling out melanoma and lymphoma. Pronounced reaction was shown for cytokeratin 20, a new histodiagnostic marker whose expression is almost entirely confined to Merkel cells, the gastric epithelium, and urothelium. The tentative diagnosis of metastasis of MCC was confirmed. Immunohistochemical studies are useful diagnostic aids in the establishment of the diagnosis of Merkel cell carcinoma.

Topics: Aged; Aged, 80 and over; Carcinoma, Merkel Cell; Cheek; Cytoplasm; Diagnosis, Differential; Facial Neoplasms; Gingival Neoplasms; Humans; Keratins; Lymphoma; Male; Mandibular Neoplasms; Melanoma; Skin Neoplasms

Epidermotropic metastases from internal malignancies are exceedingly rare. We report two examples of epidermotropic metastatic breast carcinoma with striking intraepidermal involvement. The first case mimicked melanoma because the neoplastic cells contained melanin and were disposed both as single units and as nests at the dermoepidermal junction and throughout the epidermis. In the second case, the neoplastic cells were seen as isolated neoplastic cells with large, pale cytoplasm scattered throughout the epidermis, closely resembling extramammary Paget's disease. Immunohistochemical studies in both cases demonstrated the epithelial nature of intraepidermal neoplastic cells, which showed an immunophenotype identical to the neoplastic cells present in the dermis: positive staining with anti-cytokeratins, CEA, EMA, and GCDFP-15 and negative with anti-S-100 protein and HMB-45. These findings ruled out the possibility of a collision lesion, or simultaneous occurrence of melanoma and metastatic breast carcinoma. Pagetoid intraepidermal spread of metastatic breast carcinoma, as in our two cases, is exceptional. We also discuss the histogenetic similarities between our findings and those of mammary and extramammary Paget's disease, as well as the differential diagnosis of other cutaneous disorders characterized by pagetoid intraepidermal spread of neoplastic cells.

Topics: Aged; Antigens, Neoplasm; Breast Neoplasms; Carcinoma; Carcinoma, Ductal, Breast; Diagnosis, Differential; Epidermis; Female; Humans; Immunohistochemistry; Keratins; Melanins; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; Paget Disease, Extramammary; Paget's Disease, Mammary; S100 Proteins; Skin Neoplasms

Keratin expression in cultured malignant melanoma cells has been studied only rarely. Moreover, no studies have reported of universality of keratin expression in human malignant melanoma cells. In this study, therefore, we analyzed keratin expression in eight cell lines. Using a low-salt aqueous solution without high salt and Triton X-100, as a washing buffer for keratin extraction, followed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and immunological analysis, we demonstrated keratin expression in all eight human malignant melanoma cell lines. The keratin polypeptide expressions common to all melanoma cells were K1, K5, K10 and K14. In addition, K8, K13, K17 and K18, respectively, were detected in individual cells. A measure of keratin expression universality in malignant melanoma cells may have implications regarding their invasive and metastatic behaviors, co-expressed with vimentin.

Topics: Electrophoresis, Gel, Two-Dimensional; Gene Expression Regulation, Neoplastic; Humans; Keratins; Melanoma; Tumor Cells, Cultured

Cytokeratin (CK) positivity has been considered a specific marker for epithelial differentiation in cytologic specimens. After observing CK reactivity in fine-needle aspirate (FNA) specimens of melanoma and sarcoma, a retrospective study of melanomas and sarcomas was undertaken to investigate the frequency of anomalous CK staining in these neoplasms. Cell block sections and/or restained smears from 36 melanomas and sarcomas were retrospectively stained for CK. An appropriate internal positive control (HMB-45), S100 protein, or vimentin) was also used to insure antigen preservation. Of the smears from 19 melanomas, five revealed focal strong CK positivity of neoplastic cells, two cases showed faint or equivocal staining, 11 cases were negative for CK, and one could not be interpreted due to inadequate controls. Of the smears from 14 sarcomas, two showed positivity for CK (one fibrosarcoma and one condrosarcoma), 11 were negative, and one had inadequate controls. The number of CK positive cells was less than that observed with the appropriate internal positive control antibodies. Destained Papanicolaou smears were superior to Diff-Quik smears for retrospective immunocytochemical stains. Cell block sections from four of the melanomas and one sarcoma demonstrated no aberrant staining. Since cytokeratin positivity occasionally is seen in nonepithelial neoplasms, its presence alone cannot be used to make a definitive diagnosis of carcinoma. Therefore, a panel of immunocytochemical stains should be utilized in diagnosis of FNA specimens.

Topics: Biopsy, Needle; Humans; Immunohistochemistry; Keratins; Melanoma; Retrospective Studies; Sarcoma

In order to determine epithelial markers in malignant melanoma in routinely processed paraffin sections and to compare the staining of primary (cutaneous) malignant melanomas and their metastases, we stained formalin-fixed paraffin sections of 13 primary and 18 metastatic malignant melanomas using the streptavidin-biotin peroxidase method by antibodies to S-100, vimentin, HMB-45, polyclonal carcinoembryonic antigen (CEA), monoclonal CEA, cytokeratins (CAM 5.2 and broad-spectrum CKKES), and epithelial membrane antigen (EMA). All primary and most metastatic malignant melanomas showed positive staining with anti-S-100, HMB-45, and anti-vimentin. Reactivity with polyclonal CEA was observed in 15 (48%) of the 31 lesions; 14 of them were metastatic. No lesion was reactive with monoclonal CEA. Significant cytokeratin (CK) staining was evident in only three (9.7%) lesions (all metastatic), which also stained specifically with anti-CK 18. EMA was observed only focally in two (6.5%) lesions. There was no correlation between epithelial markers staining of the primary tumours and their metastases. All lesions with CK or EMA staining showed concomitant extensive staining for S-100, HMB-45, and vimentin. We conclude that (a) polyclonal CEA staining in malignant melanoma is not rare and is probably due to CEA-related molecules; (b) significant CK reactivity is rare and related to simple CK, such as CK 18; (c) epithelial marker reactivity is more common in metastases of malignant melanomas and is not correlated to the reactivity in their primary tumors. Considering our results and reports of positive S-100, vimentin, and HMB-45 in epithelial tumors, a wide panel of antibodies is recommended for the study of undifferentiated tumors.

Topics: Adult; Antigens, Neoplasm; Biomarkers, Tumor; Carcinoembryonic Antigen; Female; Humans; Immunohistochemistry; Keratins; Male; Melanoma; Melanoma-Specific Antigens; Membrane Glycoproteins; Mucin-1; Mucins; Neoplasm Proteins; S100 Proteins; Skin Neoplasms; Vimentin

Nail pathology shares some common features with skin pathology, but it also has its own peculiar aspects. The anatomical and physiological characteristics of the nail unit probably play a major role in determining these pathological differences. Although the presence of keratohyaline granules is a normal feature of the skin, there is no granular layer in the normal nail matrix. As a consequence, nail matrix hypergranulosis should be considered a separate entity from skin hypergranulosis. In our review of 150 longitudinal nail biopsy specimens, keratohyaline granules were seen in the nail matrix of 24 cases of lichen planus, 29 cases of spongiotic trachyonychia, 10 cases of psoriasis, and three cases of Hallopeau acrodermatitis. In all cases, the presence of keratohyaline granules was associated with the absence of the normal keratogenous zone. Similar nail matrix features were detectable in three cases of malignant melanoma, two cases of primary systemic amyloidosis, and one case of histiocytoid hemangioma compressing the nail matrix. Our data suggest that inflammatory and compressive insults to the nail matrix cause both disappearance of the keratogenous zone and matrix keratinization with the formation of keratohyaline granules. Skin hypergranulosis reflects a hyperplasia of a normal skin component. In the nail matrix, however, hypergranulosis represents the appearance of structures not normally present. Nail matrix hypergranulosis should be considered a pattern of nail matrix reaction to different inflammatory insults. It is therefore more analogous to epidermal parakeratosis than to epidermal hypergranulosis.

Topics: Acrodermatitis; Amyloidosis; Biopsy; Epidermis; Epithelium; Hemangioma; Humans; Hyalin; Hyperplasia; Keratins; Keratosis; Lichen Planus; Melanoma; Nail Diseases; Nails; Onychomycosis; Psoriasis

The presence of immunoreactive neurofilament proteins has previously been reported in Merkel cell carcinomas but not in normal human epidermal and dermal Merkel cells. We have studied the immunoreactivity of epidermal Merkel cells for neurofilament triplet proteins (68 KD, 70 KD, 160 KD, 200 KD), using epidermal sheets prepared from the plantar skin of human adults, which enabled us to survey large numbers of Merkel cells. Neurofilament protein 200 KD-positive cells were readily identified, while neurofilament protein 68 KD-, 70 KD- and 160 KD-positive cells were largely absent. 200 KD-positive cells in the epidermis were confirmed to represent Merkel cells by a sequential immunoenzyme labeling for the simple epithelial type cytokeratin (No. 8). 200 KD-positive cells were 5.9% of the total number of epidermal Merkel cells. Despite a heterogeneous expression of neurofilament protein subspecies between the normal and transformed Merkel cells, the presence of neurofilament proteins in epidermal Merkel cells may link them to Merkel cell carcinomas.

Topics: Adult; Carcinoma, Merkel Cell; Cell Transformation, Neoplastic; Dendrites; Epidermis; Epithelium; Gene Expression; Humans; Immunohistochemistry; Keratins; Mechanoreceptors; Melanoma; Nerve Tissue Proteins; Neurofilament Proteins; Nevus, Pigmented; Skin; Skin Neoplasms

Atypical fibroxanthoma is a bizarre, cytologically malignant but usually clinically benign, lesion which typically arises in sun-damaged skin of the head and neck region in the elderly. Classically, its morphology is said to represent the dermal counterpart of pleomorphic malignant fibrous histiocytoma. We have identified 10 cases of a more monomorphic spindle-celled, fascicular variant which, paradoxically, was often mistaken for a clinically malignant lesion because it lacked the pleomorphism of conventional atypical fibroxanthoma. These tumours all arose in the head and neck region as polypoid lesions in the elderly. The tumours were confined to the dermis, often had an epidermal collarette, showed an eosinophilic fascicular morphology and were highly mitotic. All 10 were vimentin positive and five showed very focal actin positivity. Desmin, keratin and S-100 protein were negative in all cases. The clinical course was benign in all cases, justifying their accurate recognition. The principal differential diagnoses are spindle cell squamous carcinoma, spindle cell melanoma and leiomyosarcoma. Immunohistochemistry plays a key role in this distinction.

Topics: Aged; Aged, 80 and over; Carcinoma, Squamous Cell; Desmin; Diagnosis, Differential; Female; Fibrosarcoma; Humans; Immunohistochemistry; Keratins; Leiomyosarcoma; Male; Melanoma; Middle Aged; Mitosis; S100 Proteins; Skin Neoplasms; Vimentin

An ulcerated tumour was removed by a Whipple's operation from the descending part of the duodenum of a 38-year-old male. The tumour cells were mainly spindle-shaped, arranged in nests and had very prominent nucleoli. A few cells contained melanin and melanosomes. Immunoreactivity for S-100 protein and focally for HMB-45 was observed. These features are diagnostic for clear cell sarcoma of tendons and aponeuroses. Because no other primary tumour could be found and the search for similar cases from the literature was unsuccessful, we believe that this tumour is the first reported clear cell sarcoma in a visceral location.

Topics: Adult; Desmin; Duodenal Neoplasms; Duodenum; Humans; Immunohistochemistry; Keratins; Male; Melanoma; S100 Proteins; Sarcoma; Soft Tissue Neoplasms; Tendons; Tomography, X-Ray Computed; Ultrasonography; Vimentin

This study compares the diagnostic reliability of conventional mucin histochemistry and immunocytochemical techniques in distinguishing mammary Paget's disease from superficial spreading malignant melanoma and primary intraepidermal carcinoma. Formalin-fixed, paraffin-embedded archival tissue was used and comprised 13 cases of mammary Paget's disease, five cases of superficial spreading melanoma, and six cases of intraepidermal carcinoma. Sections from each case were stained for the presence of mucin using diastase periodic-acid-Schiff (d-PAS) with and without an alcian blue counterstain as well as immunocytochemistry for cytokeratin (CAM 5.2), epithelial membrane antigen (NCRC-11) and c-erb B-2 (21N). Mucin staining in intraepidermal carcinoma and malignant melanoma was consistently negative. Diastase-resistant PAS positivity was seen in six of 13 cases of mammary Paget's disease and eight of 13 cases using an alcian blue counterstain. NCRC-11 showed positive immunoreactivity in four of six cases of intraepidermal carcinoma, one in five cases of melanoma, and five of 13 cases of mammary Paget's disease. Positive immunoreactivity using CAM 5.2 and 21N was seen in all cases of mammary Paget's disease, with consistent negative immunoreactivity in the other tumor types. We conclude that CAM 5.2 and 21N should be used in the investigation of mammary Paget's disease in preference to conventional mucin stains.

Topics: Antibodies, Monoclonal; Breast; Breast Neoplasms; Carcinoma in Situ; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Keratins; Melanoma; Membrane Glycoproteins; Mucin-1; Mucins; Paget's Disease, Mammary; Proto-Oncogene Proteins; Receptor, ErbB-2

Several protein markers, including vimentin, have been used to diagnose human melanoma. Because melanoma often has metastasized by the time of diagnosis, early markers prognostic for metastatic potential need to be identified. Commonly, vimentin is found in mesenchymal cells, and keratins are present in epithelial cells, but recent studies report coexpression of vimentin and keratin(s) in epithelial and nonepithelial neoplasms, including some melanomas.. Our purpose was to determine whether coexpression of vimentin and keratin(s) is correlated with tumor cell invasion and metastatic behavior.. We evaluated nine human melanoma cell lines expressing vimentin and other markers of aggressive tumor behavior (HMB-45, S-100, HLA-ABC class I and HLA-DR class II histocompatibility antigens, and K8 and K18 keratins). Levels of K8 and K18 keratins were determined in the highly metastatic C8161 cell line, the poorly metastatic A375P line, and the moderately metastatic A375M line. To determine whether the presence of keratin affects migratory ability, we altered the conformational structure of keratin filaments in C8161 cells by transfection with a mutant K18 complementary DNA. We also determined messenger RNA levels of human type IV collagenase, an enzyme marker for invasion and metastasis.. In A375P cells, two-dimensional electrophoresis with Coomassie-stained gels, immunoblotting, and immunofluorescence staining showed no detectable levels of K8 or K18. A375M cells showed low levels of K8 and K18 by Western and Northern blotting, with a distinctive fluorescent subpopulation of cells. In comparison, K8 and K18 levels in C8161 cells were high in all cells. Type IV collagenase messenger RNA levels were lowest in A375P cells and highest in C8161 cells, correlating with invasive ability in vitro and metastatic potential in athymic nude mice. The transfectant clones C1070-10 and C1070-14 derived from the C8161 parent line showed dramatic morphological changes, disrupted keratin filaments, and decreased invasive and metastatic potential directly correlated with a reduction in migratory activity.. These findings show a correlation between the coexpression of vimentin with K8 and K18 keratins and the invasive and metastatic behavior of three representative human melanoma cell lines.

Topics: Animals; Humans; Keratins; Matrix Metalloproteinase 9; Melanoma; Mice; Mice, Nude; Microbial Collagenase; Neoplasm Invasiveness; Neoplasm Metastasis; RNA, Messenger; Tumor Cells, Cultured; Vimentin

A group of 52 patients with malignant uveal melanoma treated by primary enucleation in 1977-1979 was studied to determine the frequency of immunoreactivity for cytokeratins (CK) in primary and metastatic melanoma, the CK types present, and the prognostic significance of CK expression. By immunohistochemistry, monoclonal antibody (MAb) V9 to vimentin reacted with all 52 formalin-fixed, paraffin-embedded primary tumors and all 31 metastases from 11 patients. MAb CAM 5.2 to CK 8 and 18 reacted with 20 and MAb CY-90 to CK 18 with 25 primary melanomas, whereas MAb KS-B17.2 and MAb CK5 to CK 18 labeled 8 and 6 tumors, respectively. Antibodies to CK 13 and CK 19 each labeled single cells in one specimen, and other CK types were not detected. In 6 primary melanomas, only a few tumor cells were immunopositive for CK 8 and 18, but in 17 cases up to one quarter, and in 2 tumors more than one quarter, of them were labeled. The positive cells were spindle, epithelioid, or intermediate in shape, and tended to be more frequent in mixed than in spindle cell melanomas. MAbs CAM 5.2 and CY-90 did not react with any of the 16 liver metastases, but labeled 7 of 15 other metastases. Metastases were somewhat more common when the primary tumor was immunoreactive for CK 8 and 18, apparently because CKs were more frequent in mixed cell melanomas. Although CK expression is of diagnostic significance and can denote low levels of epithelioid differentiation, it is not an independent prognostic factor in malignant uveal melanoma.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal; Female; Humans; Immunoenzyme Techniques; Immunohistochemistry; Keratins; Male; Melanoma; Middle Aged; Prognosis; Retrospective Studies; Uveal Neoplasms

Microwave-stimulated chemical fixation has been used successfully to rapidly prepare nonocular tissue for processing and paraffin embedding.. This same technique was adapted to fix whole eyes using a common domestic microwave oven. Histologic sections were compared with sections from globes that were fixed in a traditional manner.. Histologic sections and histochemical and immunohistochemical staining of eyes treated with microwave-stimulated chemical fixation in 10% neutral-buffered formalin were comparable in quality to eyes fixed in 10% neutral-buffered formalin at room temperature for 48 hours.. Because microwave irradiation accelerates the most time-consuming part of preparing whole eyes for light microscopy, the technique enhances laboratory efficiency. The technique is particularly well suited for ensuring adequate fixation of globes when histologic diagnosis is needed in less than 48 hours.

Topics: Animals; Buffers; Choroid Neoplasms; Dogs; Eye; Eye Neoplasms; Fixatives; Formaldehyde; Humans; Immunoenzyme Techniques; Keratins; Macaca; Melanoma; Microwaves; Rabbits; Retinoblastoma; Tissue Fixation

The ability of a panel of monoclonal antibodies generated in this laboratory to identify "pagetoid" melanoma cells and distinguish them from true Paget's adenocarcinoma cells in a retrospective analysis of vulvar neoplasms was investigated. Paraffin blocks of formalin and Carnoy's fixed tissue from 15 cases of vulvar Paget's disease and 11 cases of primary vulvar melanoma were retrieved and sections were incubated with the following panel of monoclonal antibodies: HMB45, a melanoma-specific monoclonal antibody; and 35 beta H11 and 34 beta E12, two different anti-cytokeratin monoclonal antibodies, to low molecular and high molecular weight cytokeratins, respectively. The anti-melanoma monoclonal antibody (HMB45) positively identified the melanoma cells, distinguishing them from normal melanocytes, in all 11 cases of melanoma. In contrast, the HMB45 antibody failed to react with the intraepithelial neoplastic cells in all cases of Paget's disease. These latter malignant cells were strongly positive only with the monoclonal anti-low molecular weight cytokeratin antibody 35 beta H11. This latter antibody absolutely distinguished tumor cells from neighboring uninvolved squamous epithelium, which was positive only with the monoclonal antibody 34 beta E12. Using this panel of monoclonal antibodies, the surgical margins could also be better evaluated; in at least one case the surgical margin thought by histological evaluation to be free of tumor was demonstrated by immunocytochemistry to be positive for tumor. In the vulvectomy specimens obtained in both diseases, Paget's or melanoma cells were identified in sections histologically interpreted as free of tumor. Thus, a panel of monoclonal antibodies is able to identify, with high sensitivity and specificity, vulvar melanoma cells and absolutely distinguish them from vulvar Paget's cells and can help in evaluating surgical margins in a more accurate manner.

Topics: Antibodies, Monoclonal; Diagnosis, Differential; Female; Humans; Immunoenzyme Techniques; Keratins; Melanoma; Molecular Weight; Paget Disease, Extramammary; Retrospective Studies; Sensitivity and Specificity; Vulvar Neoplasms

A 58-year-old man was seen with obstructive jaundice and discomfort in the upper abdomen. Computed tomographic and ultrasound examinations revealed a soft-tissue mass in the gallbladder. Cholecystectomy and choledochotomy revealed a soft black mass in the gallbladder and a second one in the intrapancreatic portion of the common bile duct. Each was diagnosed as malignant melanoma. Subsequently, a Whipple resection of the pancreas, duodenum, and distal bile duct revealed a melanoma circumferentially invading and obstructing the distal common duct. No lymph node or distant metastasis was identified. Repetitive searches for another primary site have been negative. The tumor apparently originated in the biliary tract. The patient remains almost well 2 years after diagnosis.

Topics: Bile Duct Neoplasms; Common Bile Duct; Gallbladder Neoplasms; Humans; Immunoenzyme Techniques; Keratins; Male; Melanoma; Middle Aged; S100 Proteins; Tomography, X-Ray Computed

Several studies have suggested that HMB-45 is a specific marker for melanoma, presumably due to its ability to detect a glycoprotein that is present in premelanosomes. The present study was conducted to evaluate whether HMB-45 is an absolutely specific antigenic determinant for melanoma and the role that testing with this antibody has in the differential diagnostic workup of amelanotic melanoma vs adenocarcinoma. Formaldehyde solution-fixed, paraffin-embedded tissue samples from 52 adenocarcinomas (primary or metastatic) and five melanomas (two primary and three metastatic) were immunostained with the use of a commercially available monoclonal antibody (MoAb), ie, HMB-45 (Enzo), a polyclonal antibody to S100 protein, a wide-spectrum keratin polyclonal antibody, and a keratin MoAb, ie, AE1/AE3. Approximately 10% (ie, 9.6%) of the adenocarcinomas (five cases) expressed HMB-45 with varied intensity and distribution. Positive primary tumors (n = 3) included one each from the breast, colon, and kidney; positive metastatic tumors (n = 2) included one each from the breast and endometrium. Fifty-two percent of the adenocarcinomas were positive for S100 protein. One renal carcinoma was negative for both keratins when tested with the AE1/AE3 MoAb and polyclonal antibody (Dako). This was the only adenocarcinoma that was negative when the keratin polyclonal antibody (Dako) was used. All but one additional adenocarcinoma demonstrated keratin expression when the AE1/AE3 MoAb was used for testing. This study showed that HMB-45 is not absolutely specific for melanoma. HMB-45 may react with some adenocarcinomas, at least when tested with the commercially available MoAb (Enzo). This fact, in conjunction with aberrant keratin expression by some melanomas and S100 protein expression by adenocarcinomas and other neoplasms other than melanomas, should be considered when antibody panels are evaluated in the workup of poorly differentiated tumors. However, HMB-45 appears to be the most specific marker that is available at the present time for supporting a diagnosis of melanoma.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Antigens, Neoplasm; Biomarkers, Tumor; Humans; Immunoenzyme Techniques; Keratins; Melanoma; S100 Proteins; Staining and Labeling

Human melanomas are known to contain vimentin intermediate filaments but there has been some dispute about their expression of cytokeratins. The cytoplasm of human M21 melanoma cells maintained in culture reacted with a rabbit anti-keratin antibody and two monoclonal anti-keratin antibodies AE1 and AE2. Cells derived directly from subcutaneous xenografts of M21 melanoma in nude mice, however, failed to express cytokeratins. The presence of keratin filaments in cultured M21 cells was confirmed by electronmicroscopic and immuno-electronmicroscopic examinations of cell extracts. Polyacrylamide gel electrophoresis (PAGE), revealed 46 KD keratin proteins in cultured M21 cells. Small amounts of these low molecular weight keratins were detected by PAGE in M21 melanoma xenografts even though immunofluorescence and immunoperoxidase assays failed to demonstrate keratin at the light microscopic level. Immunofluorescence revealed keratin and carcinoembryonic antigen (hitherto undetected in human melanomas) first on the 9th day of culture of xenograft-derived M21 cells. The appearance of keratin and CEA in M21 melanoma cells in vitro was not affected by inhibition of cellular proliferation or as a result of exposure to methotrexate or adriamycin. However, adriamycin altered the cytoplasmic distribution of keratin.

Topics: Antibodies, Monoclonal; Carcinoembryonic Antigen; Cell Extracts; Doxorubicin; Fluorescent Antibody Technique; HeLa Cells; Humans; Immunodiffusion; Immunohistochemistry; Keratins; Melanoma; Methotrexate; Microscopy, Electron; Transplantation, Heterologous; Tumor Cells, Cultured

To determine whether ocular melanomas are immunophenotypically identical to cutaneous melanomas, 34 primary and metastatic choroidal melanomas representing all major histotypes defined by the Callender's classification, plus one melanoma of the iris and one conjunctival melanoma, were subjected to a panel of immunostains designed to distinguish anaplastic biopsies of cutaneous melanomas from carcinomas and lymphomas. All ocular melanomas were found to express the intermediate filament vimentin but not keratin, and all but 2 were melanotic by immunostaining. Thirty-three of 34 (97%) choroidal melanomas were strongly stained with a rabbit polyclonal antibody (P-S100) developed against the S100 protein family. In contrast, none of 14 spindle cell type primary lesions was stained with a monoclonal antibody (MAB-079) specific for both S100 alpha and S100 beta, the best-characterized S100 polypeptides. Furthermore, only 2 of 5 epithelioid and 3 of 10 mixed-cell-type melanomas were weakly reactive. Overall, 14.7% (5 of 29) were stained. In comparison, MAB079 stained 85% of all cutaneous melanomas. Five metastases of choroidal melanomas (spindle B, epithelioid, and mixed cell types) from different organ sites also were stained by P-S100 but not by MAB079. These findings were corroborated by immunostaining with another monoclonal antibody (MAB4D4) specific for S100 beta. Differential staining by the polyclonal but not the monoclonal antibodies suggests the possible presence of a variant S100 polypeptide(s) in choroidal melanomas. Since S100 alpha, S100 beta, and related proteins appear to be physiologically important, additional studies of these S100 proteins may shed light on the etiology or pathology of choroidal melanomas.

Topics: Antibodies, Monoclonal; Chi-Square Distribution; Conjunctival Neoplasms; Humans; Immunoenzyme Techniques; Iris Neoplasms; Keratins; Melanoma; Phenotype; S100 Proteins; Skin Neoplasms; Uveal Neoplasms; Vimentin

Although many reports on chromosome changes in human malignant melanoma (HMM) have been published, it is still impossible to define the significance of the different markers reported. In fact, we think that the difficulties in interpreting the chromosomal abnormalities could be due to poorly defined clinical conditions and a lack of correlation with cytological and histological analyses. To verify this hypothesis, we studied 10 cell lines obtained from 8 patients affected by cutaneous malignant melanoma that were well defined for their clinical, histologic, and cytogenetic aspects. No significant correlation was found among these parameters, and, hence, the cytogenetics findings cannot be used to determine a more detailed diagnosis or a more definite prognosis.

Topics: Chromosome Aberrations; Humans; Keratins; Melanoma; Tumor Cells, Cultured; Vimentin

Immunohistochemical characterization is an accepted method of human cell typing and tumor diagnosis. The differentiation of undifferentiated carcinoma from amelanotic melanoma is usually achieved by demonstration of cytokeratin (CK) intermediate filaments in carcinoma but not in melanoma. In examination of 100 melanomas fixed in formalin or methacarn and frozen tissue sections, we have found CK-immunoreactivity in 2, 8, and 21% of cases, respectively, with multiple anticytokeratin antibodies displaying overlapping antigenic specificities. In addition, we have confirmed the anomalous expression of low molecular weight CK proteins by one- and two-dimensional gel electrophoresis and immunoblotting of extracts of an immunohistochemically positive case. This latter finding indicates that CK staining in melanomas reflects the presence of authentic CK peptides and is not an artefact induced by fixation or cross-reacting antibodies. These observations have direct implications for the application of immunohistochemistry to the present practice of diagnostic surgical pathology. The anomalous CK expression by melanoma limits the diagnostic reliability of immunohistochemically demonstrated CK alone to indicate a diagnosis of carcinoma, without the concomitant detection of additional tumor-associated antigens. The finding of anomalous CK expression only in metastatic or recurrent melanomas raises an interesting question of possible association with tumor progression.

Topics: Blotting, Western; Electrophoresis, Gel, Two-Dimensional; Electrophoresis, Polyacrylamide Gel; Humans; Immunoenzyme Techniques; Keratins; Melanoma; Retrospective Studies

We report four unusual cases of malignant melanoma in which squamous cell carcinoma was strongly considered in the differential diagnosis on routine hematoxylin and eosin-stained sections due to the near absence of melanin and the presence of pseudocarcinomatous hyperplasia. Ultimately, immunohistochemical staining for S-100 protein and keratin established the correct diagnosis of malignant melanoma in all cases.

Topics: Aged; Carcinoma, Squamous Cell; Diagnosis, Differential; Female; Humans; Hyperplasia; Immunohistochemistry; Keratins; Male; Melanoma; Middle Aged; S100 Proteins; Skin; Skin Neoplasms

We have tested the diagnostic value in malignant melanoma of HMB45, a monoclonal antibody available for use on paraffin-embedded tissue. MATERIAL AND METHOD. Tissues tested. The following pathological tissues were tested: 10 intradermal and 11 compound naevi; 6 spitz naevi; 20 dysplastic naevi; 10 blue naevi; 2 Bednar's tumours; 6 Sutton naevi; 15 melanonychias; 21 cutaneous and 11 ocular malignant melanomas (MM), and 3 achromic metastases. Control tissues were: vitiligo (20), carcinoma (5), malignant schwannoma of the orbit (1), soft tissue sarcoma (5) and malignant lymphoma (5). Antibodies. The antibodies used were antiprotein S100, antivimentin, anticytokeratin (KL1), monoclonal antileucocyte (CD45) antibodies and HMB45, a monoclonal antibody of the IgG 1 type obtained from lymph node metastases from pigmented malignant melanomas. RESULTS. None of the control tissues were stained by the HMB Ab. Intradermal naevi did not react positively. Compound naevi: the juntional cells were stained by HMB45 in 2/10 cases. Dysplastic naevi: HMB45 showed heterogeneous reactivity of junctional cells in 15/20 cases, and this correlated with the degree of atypia. Blue naevi: HMB45 stained the superficial and deep cells in 3/10 cases. Bednar's tumour: no cell was stained by HMB45. Spitz naevi: HMB45 gave an intensely positive reaction of junctional cells in 4/5 cases and a weaker reaction of dermal cells. Sutton naevi: the naevus cells were not stained by HMB45 in 5/6 cases. In simple melanocytic hyperplasia of the nail bed, only a few atypical cells were stained. In superficially spreading melanoma (SSM) all neoplastic cells were stained by HMB45 in proportion to their degree of atypia. Residual naevus cells were negative. The anti S100 and the antivimentin antibodies stained all neoplastic and naevus cells. In nodular melanoma (NM), HMB45 stained all neoplastic cells in proportion to their degree of atypia. The antivimentin Ab stained the neoplastic cells, and so did the anti-S100 Ab which also stained inflammatory cells. In acral-lentiginous melanoma (ALM), HMB stained the dermal tumoral cells moderately and the junctional cells more strongly. In ocular melanoma, HMB45 strongly stained the fusiform cells and less strongly the epithelioid cells. In achromic metastases from cutaneous malignant melanomas, HMB45 strongly stained the neoplastic cells but did not stain the peritumoral cells. DISCUSSION. The purpose of this study was to compare the value of HMB45 with that o

Topics: Antibodies, Monoclonal; Eye Neoplasms; Humans; Immunoenzyme Techniques; Keratins; Leukocytes; Melanoma; Nevus, Pigmented; S100 Proteins; Skin Neoplasms; Vimentin

Specimens of neoplastic tissues from 19 dogs and 4 cats were examined immunohistochemically for intermediate filament expression, using commercially available antibodies. Staining was observed in a wide range of tumor tissues and in normal internal controls by use of antibodies to vimentin, desmin, glial fibrillary acidic protein, and low and high molecular weight cytokeratins. Intermediate filament expression was found to be consistent with light and/or electron microscopic findings, and hence believed to be an accurate indicator of tumor histogenesis in cats and dogs. Three fixatives were evaluated for their relative abilities to preserve antigenicity. Absolute alcohol was superior to B5 fixative and both were superior to formalin. Some tissues that clearly displayed intermediate filament antigens with alcohol and B5 fixative failed to stain when fixed in formalin.

Topics: Adenocarcinoma; Animals; Astrocytoma; Cat Diseases; Cats; Cytoskeleton; Desmin; Dog Diseases; Dogs; Immunohistochemistry; Intermediate Filament Proteins; Intermediate Filaments; Keratins; Leiomyosarcoma; Melanoma; Neoplasms; Neurilemmoma

The ultrastructural feature of keratinocytes was investigated in human superficially spreading melanomas of type B. The tumor cells of these melanomas are characterized by spheroidal melanosomes and containing pheomelanins. Contrary to type A melanomas the keratinocytes show no striking transformation reaction neither in the nucleus nor in the cytoplasm although this part of the cell mostly contains abundant melanin granules surrounding the nucleus. Whether there exists a relation to the clinical course still has to be clarified.

Topics: Epidermis; Histocytochemistry; Humans; Keratins; Melanocytes; Melanoma; Microscopy, Electron; Skin Neoplasms

Immunoperoxidase techniques for S-100 protein, keratin, cytokeratin, vimentin and desmin were applied to 65 canine skin tumours. These included eight squamous cell carcinomas, eight fibrosarcomas, eight melanomas, eight mastocytomas, eight haemangiosarcomas, eight leiomyosarcomas, five liposarcomas and 12 poorly differentiated tumours. Consistent results were obtained within each group. Cytokeratin and keratin immunoreactivity was detected only in squamous cell carcinomas. Vimentin was present in fibrosarcomas, melanomas, haemangiosarcomas, mastocytomas, leiomyosarcomas and liposarcomas. S-100 protein immunoreactivity was detected in melanomas, haemangiosarcomas, liposarcomas and leiomyosarcomas. Only leiomyosarcomas were positive for desmin. According to these results the 12 anaplastic tumours were diagnosed either as carcinomas, fibrosarcomas or malignant melanomas.

Topics: Animals; Carcinoma, Squamous Cell; Desmin; Dog Diseases; Dogs; Fibrosarcoma; Hemangiosarcoma; Immunoenzyme Techniques; Keratins; Leiomyosarcoma; Liposarcoma; Mast-Cell Sarcoma; Melanoma; S100 Proteins; Skin Neoplasms; Vimentin

Azelaic acid (AZA) has been reported to have an inhibitory effect on DNA synthesis of melanoma cell lines. In order to elucidate the mechanism(s) underlying this inhibitory effect, I elected to study the effects of AZA and, for control purposes, adipic acid (ADA) on DNA synthesis rate of nuclei isolated from melanoma cells and keratinocytes cultured in the presence of different concentrations of the dicarboxylic acids. Before doing so, I found, by autoradiography, that [3H]AZA is incorporated into the nuclei in a time-dependent manner. AZA, and to a lesser extent ADA, caused a dose-dependent inhibition of DNA synthesis, regardless of whether these substances were present in cell cultures before isolation of nuclei, or were incubated with already isolated nuclei. In searching for the target for this inhibitory effect on nuclear DNA synthesis, I found that AZA, and to a lesser extent ADA, is a potent inhibitor of both bacterial DNA polymerase and of multienzyme complexes isolated from cultured melanoma cells and keratinocytes. These data suggest that the inhibitory effect of the dicarboxylic acids AZA and ADA on DNA synthesis of several cell lines is due to the interference of these substances with the activation of enzymes (e.g. DNA polymerases) required for DNA synthesis.

Topics: Adipates; Animals; Cell Line; Cell Survival; Dicarboxylic Acids; DNA; Epidermal Cells; Epidermis; Humans; Keratins; Melanoma; Nucleic Acid Synthesis Inhibitors; Tumor Cells, Cultured

Acetone-fixed frozen sections of 15 malignant melanomas of the skin with metastases were studied immunohistochemically for the presence of different types of intermediate filament proteins, synaptophysin, muscle cell actins, and desmoplakins. One of the melanomas was a primary toe tumor, and the others mainly regional lymph node metastases. The original diagnosis of melanoma was reconfirmed in each case, and the melanoma diagnosis of the metastases was verified by S100 protein immunostaining in all cases and by a monoclonal antibody to melanoma cells (NK1C3) in 7 cases. All melanomas were prominently vimentin-positive. In 10 of 15 cases, immunoreactive keratin could be demonstrated with antibody CAM 5.2. The presence of keratins was confirmed in selected cases with three other monoclonal antibodies including AE1, PKK1, and a monoclonal antibody specific for keratin number 18. Desmoplakin, another marker of epithelial differentiation, was not found in melanoma cells. Two melanomas contained neurofilament-positive tumor cells, which were however negative for synaptophysin. Desmin, muscle actins, and glial fibrillary acidic protein were not found in the neoplastic cells. On the basis of the present results one could conclude that the protein composition of the cytoskeleton of melanomas is more complex than has been previously thought and most importantly that melanomas may contain keratins.

Topics: Adult; Aged; Cell Transformation, Neoplastic; Female; Humans; Immunohistochemistry; Intermediate Filaments; Keratins; Male; Melanoma; Middle Aged; Skin Neoplasms

Regarding the keratin pattern of non-exposed skin, we found no significant qualitative or quantitative differences between 6 old persons (mean age 85 years) and 4 young adults (mean age 20 years). There was, however, a slight increase of proliferation keratins (K6, K16) in aged skin. In non-exposed skin taken from 6 old (mean age 70 years) and 5 young persons (mean age 37 years), longterm primary submersion cultures of keratinocytes did not show any significant differences as far as the classical parameters of growth behavior were concerned (i.e. plating efficiency, cell count, and labeled thymidine incorporation). In accordance with these findings, daily measurements of the thymidine kinase activity in the supernatants revealed discrete but not significant differences between keratinocytes in aged people and those in young persons.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biopsy; Cell Division; DNA Replication; Female; Humans; Keratinocytes; Keratins; Male; Melanoma; Middle Aged; Skin Aging; Skin Neoplasms

A 24 year-old male with painful swelling over the right side of his palate for about two weeks was presented. An incisional biopsy was performed. In a routine hematoxylin and eosin examination by light microscopy, spindle and epithelioid cells with a bizarre appearance were discernible in the submucosal area. A pagetoid pattern was found in areas of the epithelium. Since this is not a remarkable finding, further examinations, such as the Trichrome-Masson and silver stain, immunohistochemistry using cytokeratin, vimentin, S-100, leukocyte common antigen, factor VIII, and alpha-1-antichymotrypsin detection kits, and electron microscopy were all carried out. According to the histological pattern of cells and the positive findings from the special stains, immunohistochemistry, and electron microscopy, a diagnosis of desmoplastic amelanotic melanoma was made. This variant of melanoma is a rare disorder with unremarkable, non-specific clinical manifestations in the oral cavity, which makes the diagnosis of this disease more difficult. We, therefore, report one case of this disease. Owing to the fact that diagnosis of this variant was mainly based on the positive findings of vimentin and S-100 in the immunohistochemistry examination and intracellular premelanosome detected by electron microscopy, immunodiagnosis and electron microscopy seem to be essential for differential diagnosis.

Topics: Adult; Diagnosis, Differential; Humans; Immunoenzyme Techniques; Keratins; Male; Melanoma; Microscopy, Electron; Palatal Neoplasms; S100 Proteins; Vimentin

We recently received in consultation a lymph node involved by metastatic malignant melanoma with unusual and previously undescribed morphologic features. The neoplastic cells had a striking signet-ring appearance, similar to the signet-ring cells normally seen in mucin-producing adenocarcinoma and signet-ring cell lymphoma. Review of our consultation files of malignant melanomas revealed an additional case in which the neoplastic cells had a signet-ring cell appearance. Electron microscopic studies revealed that formation of signet-ring cells is caused by the presence of abundant vimentin filaments in the cytoplasm of neoplastic cells. Immunologic studies using a series of monoclonal and polyclonal antibodies, including S-100 protein, HMB-45, vimentin, cytokeratin, leukocyte common antigen, and Leu-M1, on both cases clearly established the diagnosis of this morphologically unusual variant of malignant melanoma for which we propose the term "signet-ring cell melanoma."

Topics: Adult; Antigens, Differentiation, T-Lymphocyte; Antigens, Neoplasm; Female; Histocompatibility Antigens; Humans; Immunohistochemistry; Keratins; Leukocyte Common Antigens; Lymph Node Excision; Lymph Nodes; Lymphatic Metastasis; Male; Melanoma; Melanoma-Specific Antigens; Middle Aged; Neoplasm Proteins; S100 Proteins; Vimentin

S-100 protein has been used as a marker of various lesions, including peripheral nerve sheath, cartilaginous and salivary gland tumors, chordomas, histiocytosis X, and melanomas, among others. The list of neoplasms that can express S-100 protein continues to expand. It has been suggested that staining for S-100 protein may be of aid in the differential diagnosis of amelanotic melanoma versus poorly differentiated tumors. Three hundred fifty primary and metastatic adenocarcinomas from various sites were immunostained for S-100 protein with the use of a commercially available polyclonal antibody. Forty-two percent of the adenocarcinomas tested expressed S-100 protein to varying degrees. The relative incidence of S-100-positive tumors varied with the primary sites, some expressing S-100 protein more often than others. A primary neoplasm able to express S-100 protein was usually associated with metastatic foci also expressing this marker. However, occasionally, a primary S-100-positive tumor was associated with metastasis that lacked expression of S-100. This study emphasizes the importance of testing for a panel of tumor markers in the evaluation of poorly differentiated tumors and cautions on possible difficulties that may arise in the interpretation of immunocytochemistry results.

Topics: Adenocarcinoma; Humans; Keratins; Melanoma; S100 Proteins

Recombinant human IFN-gamma, used for treatment of melanoma and renal carcinoma, was found to induce HLA-DR expression on human keratinocytes in vivo. HLA-DR antigens bound to keratinocytes of the basal and suprabasal layers of the epidermis were observed after intramuscular or intravenous injections of 0.5 mg/kg body weight IFN-gamma, 3 times a week. Keratinocyte-bound HLA-DR antigens were first observed at the beginning of the third or fourth week of treatment, but HLA-DQ and HLA-DP antigens were never detected on keratinocytes. The intracytoplasmic constant (gamma) chain of the class II molecules was also not detectable within the keratinocytes. Patients who received IFN-alpha 2 therapy, did not exhibit keratinocyte-bound HLA-DR antigens.

Topics: Female; HLA-DR Antigens; Humans; Interferon-gamma; Keratins; Kidney Neoplasms; Male; Melanoma; Recombinant Proteins; Skin

Topics: Epidermis; Humans; Interferon-gamma; Keratins; Melanoma; Prostaglandins E; Skin Neoplasms

In this study we examined 198 sarcomas, 38 carcinomas, 13 'tumours with a spindle cell component' and 22 malignant melanomas with a commercial monoclonal vimentin antibody. All histopathological material was formalin fixed and paraffin embedded. The results show this antibody to be a sensitive and specific marker of mesenchymal derivation or differentiation. It is a useful tool in separating sarcomas from most carcinomas, and in separating malignant melanomas from carcinomas. When used in combination with a cytokeratin antibody it identifies carcinosarcomas and synovial sarcomas.

Topics: Antibodies, Monoclonal; Carcinoma; Carcinosarcoma; Diagnosis, Differential; Humans; Immunoenzyme Techniques; Keratins; Melanoma; Neoplasms; Retrospective Studies; Sarcoma; Vimentin

This study compares the immunoprofiles of 25 cutaneous and mucosal melanomas with those of 400 poorly differentiated carcinomas, using a polyclonal antiserum to S100 and murine monoclonal antibodies to keratin (KER) and epithelial membrane antigen (EMA). All malignant melanomas expressed S100 but lacked reactivity for KER and EMA. Conversely, all of 49 carcinomas (12%) that displayed S100 also exhibited positivity for both epithelial markers. The latter group of tumors included 17 carcinomas of the breast, 16 eccrine sweat gland carcinomas, five high-grade salivary glandular adenocarcinomas, four lung cancers, three pancreatic ductal carcinomas, two serous ovarian carcinomas, one clear cell adenocarcinoma of the bladder, and one uterine cervical squamous carcinoma. None of 32 epithelial neoplasms that lacked both KER and EMA (19 testicular seminomas, four hepatocellular carcinomas, eight adrenocortical carcinomas, and one Merkel's cell carcinoma) contained S100 protein. These results suggest that S100 protein is relatively nonspecific as a single immunodeterminant in the diagnostic separation of melanoma and anaplastic carcinoma. The concomitant use of stains for EMA and KER, however, obviates this problem. Finally, since it is somewhat restricted in distribution, S100 reactivity in a known carcinoma may be of some use in predicting possible primary sources for a metastasis of unknown origin.

Topics: Carcinoma; Diagnosis, Differential; Histocytochemistry; Humans; Immunoenzyme Techniques; Keratins; Melanoma; Membrane Proteins; Mucin-1; Neoplasm Proteins; Predictive Value of Tests; S100 Proteins

The differentiation of Paget's disease from Bowen's disease and Pagetoid superficial spreading melanoma may represent diagnostic difficulties. The special stains used in their differential diagnosis are nonspecific and not always sensitive. Therefore, the expression of cytokeratins of different molecular weights (54, 57, and 66 kilodaltons [kD]) was studied in 26 intraepithelial neoplasms in formalin-fixed paraffin-embedded tissues with the use of an avidin-biotin complex (ABC) method with monoclonal cytokeratin antibodies. These included 9 cases of Paget's disease, 11 cases of Bowen's disease, and 6 cases of Pagetoid superficial spreading melanoma. Paget cells from vulva and breast were always positive for 54-kD cytokeratin, variable for 57-kD cytokeratin, and negative for 66-kD cytokeratin. The neoplastic cells in all 11 cases of Bowen's disease were stained for 57-kD and 66-kD cytokeratins but not for 54-kD cytokeratin. The neoplastic cells in all cases of melanoma did not express any of the cytokeratins studied. The results indicate that antibodies to cytokeratins of different molecular weights may be used as a diagnostic tool in the distinction of Paget's disease from Bowen's disease and melanoma.

Topics: Antibodies, Monoclonal; Bowen's Disease; Breast; Carcinoma, Intraductal, Noninfiltrating; Carcinoma, Squamous Cell; Female; Humans; Keratins; Melanoma; Paget Disease, Extramammary; Paget's Disease, Mammary; Skin; Skin Neoplasms; Vulvar Neoplasms

Expression of intermediate filament (IF) isotypes was studied in six human and two murine melanoma cell lines. With one exception, these lines expressed IFs only of the vimentin type; neurofilament peptides, desmin and GFAP were not detected. However, the M5 human melanoma line also expressed extensive cytokeratin tonofilament arrays, as visualized by immunofluorescence with a panel of eleven monoclonal antibodies and hetero-antisera to cytokeratins; only the keratin 19-specific antibody BA16 did not react. By 2 D gel electrophoresis, five major keratin peptides were detected (keratins 7, 8, 13, 17 and 18), and an additional 57 kD peptide was detected on immunoblots with several antikeratin antibodies. Also observed in M5 cells was focal collapse of tonofilament arrays in mitotic cells. All the melanoma lines tested were positive for S100; M5 and two other cell lines were also positive for the 220-240 kD neuroectoderm-associated cell-surface differentiation antigen defined by monoclonal antibody UJ 127:11. In all the melanoma cell lines, secretion of extracellular matrix proteins (fibronectin, laminin and collagen type IV) was sparse or absent, and all were negative for the epithelial cell markers HMG-1 and HMG-2. Co-expression of keratin and vimentin by a melanoma cell line is discussed in the light of recent controversy concerning expression of cytokeratins by other neoplasms of putative neuroectodermal origins.

Topics: Antibodies, Monoclonal; Antibodies, Neoplasm; Cell Line; Chromatography, Gel; Extracellular Matrix; Humans; Immunoelectrophoresis; Intermediate Filament Proteins; Keratins; Melanoma; Neoplasm Proteins; Phenotype; Vimentin

The thrombolytic effect of guinea pig keratocyte plasminogen activator was evaluated in rabbits with experimental jugular vein thrombosis and compared with human melanoma activator. Both the activators were infused locally at two dose levels in groups of three rabbits. Infusion of 6,000 and 16,000 I.U./rabbit over 4 hr resulted in 43 and 62% lysis with guinea pig keratocyte activator whereas melanoma activator induced 59 and 66% lysis with 6,000 and 12,000 I.U./rabbit. Thrombolysis with both these activators was not associated with systemic activation of the fibrinolytic system or fibrinogen breakdown. It is concluded that the guinea pig keratocyte activator is a specific thrombolytic agent with an in vivo potency very similar to the melanoma activator.

Topics: alpha-2-Antiplasmin; Animals; Disease Models, Animal; Epithelium; Fibrinogen; Fibrinolysis; Fibroblasts; Humans; Keratins; Melanoma; Partial Thromboplastin Time; Phlebitis; Plasminogen Activators; Rabbits; Rats

Paraffin sections of formalin-fixed tumor samples from 26 patients with neuroendocrine (Merkel cell) carcinoma of the skin (NECS) were studied immunohistochemically with three monoclonal antibodies to low molecular weight keratin (MAB-K) and with antibodies to leukocyte common antigen (LCA), neurofilament (NF), neuron-specific enolase (NSE), S100 protein (S100), and chromogranin (CGN), to investigate the relative diagnostic value of these antibodies. Samples from 20 lymphomas, 10 non-oat cell undifferentiated carcinomas, 10 oat cell carcinomas, and 10 melanomas served as controls. Keratin was found in 25 of the 26 NECS and in all undifferentiated and oat cell carcinomas. A ball-like immunostaining for keratins, resembling an inclusion body was seen only in cases of NECS and some carcinoids. Neurofilament, NSE, and CGN were expressed by fewer NECS than was keratin and all NECS were negative for LCA and S100. None of the lymphomas and melanomas contained detectable keratin, NF, NSE, or CGN. Only the lymphomas stained with LCA. Only the melanomas were S100-positive. It is concluded that keratin is the most useful single discriminating marker in the separation of neuroendocrine (Merkel cell) carcinoma of the skin from lymphoma, melanoma and, when the characteristic inclusion-like pattern is seen, from metastatic oat cell carcinoma.

Topics: Adult; Aged; Antibodies, Monoclonal; Carcinoid Tumor; Carcinoma; Carcinoma, Small Cell; Diagnosis, Differential; Female; Gastrointestinal Neoplasms; Histocytochemistry; Humans; Immunochemistry; Keratins; Lung Neoplasms; Lymphoma; Male; Melanoma; Microscopy, Electron; Middle Aged; Nerve Tissue Proteins; Skin Neoplasms

Different tumours of the head and neck were analysed by immunohistochemistry. The distribution pattern of several intermediate filaments was studied. Keratin filaments were typical of carcinomas, whereas vimentin filaments were typical of mesenchymal tumours of different origin. The advances of this new technique of "tumour typing" are discussed.

Topics: Carcinoma, Basal Cell; Cytoskeleton; Diagnosis, Differential; Head and Neck Neoplasms; Humans; Hypopharyngeal Neoplasms; Immunoenzyme Techniques; Intermediate Filaments; Keratins; Lymphoma; Melanoma; Mouth Neoplasms; Nasopharyngeal Neoplasms; Neuroma, Acoustic; Oropharyngeal Neoplasms; Tonsillar Neoplasms; Vimentin

The malignant intraepithelial proliferations--malignant melanoma level I, bowenoid epithelial dysplasia, and mammary as well as extramammary Paget's disease--may cause differential diagnostic difficulties. We have examined 12 cases of malignant melanoma level I, nine cases of bowenoid epithelial dysplasia, 17 cases of extramammary and five cases of mammary Paget's disease for S100 protein, carcinoembryonic antigen (CEA), cytokeratin, and keratin to evaluate the sensitivity and specificity of these reactions with regard to their differential diagnostic value. Antibodies against S100 reacted specifically with the tumor cells in intraepithelial malignant melanomas; antibodies against CEA reacted specifically with the tumor cells in Paget's disease; and cytokeratin and keratin antibodies reacted with the epithelial tumor cells in Paget's disease as well as in bowenoid epithelial dysplasia. However, only antibodies to CEA and keratin showed 100% sensitivity. We conclude that the investigated antibodies may be of differential diagnostic value in cases of intraepidermal neoplasias, but that a negative reaction does not exclude diagnosis of these diseases.

Topics: Bowen's Disease; Breast Neoplasms; Carcinoembryonic Antigen; Carcinoma; Diagnosis, Differential; Humans; Immunologic Techniques; Keratins; Melanoma; Paget Disease, Extramammary; Paget's Disease, Mammary; Retrospective Studies; S100 Proteins; Skin Neoplasms

Epithelial sheets can be cultivated from isolated epidermal cells; in this way, it is possible to increase the cell number considerably. H. Green and co-workers were the first to make use of such epithelia for the autologous covering of burn wounds. We modified this method and report on our experiences with this technique in a patient with small skin defects.

Topics: Adult; Burns; Epithelium; Female; Humans; Immunoenzyme Techniques; Keratins; Melanoma; Skin Neoplasms; Skin Transplantation; Vimentin; Wound Healing

Two hundred and three sarcomas, 40 carcinomas, 10 carcinomas with spindle cell features, 27 malignant melanomas and one spindle cell melanoma were examined using CAM 5.2, a monoclonal antibody to cytokeratin. This antibody which was prepared against colorectal carcinoma cells and which identifies low molecular weight intermediate filament cytokeratin proteins is suitable for use in formalin fixed, paraffin embedded material. Seventeen of the 203 sarcomas showed positive staining. These included 15/21 synovial sarcomas, 1/5 epithelioid sarcomas and 1/18 malignant neural tumours. Five carcinosarcomas showed positive staining of their epithelial components but negative staining of their spindle cell components; three out of four pure spindle cell carcinomas stained positively; a metastasis from a spindle cell renal carcinoma was negative. A spindle cell thymoma also stained positively. Thirty-seven of the 40 carcinomas stained positively; the three negative carcinomas were a squamous cell carcinoma, a renal cell carcinoma and an oat cell carcinoma. All malignant melanomas were negative. These results are compared with those of other workers and the sensitivity and specificity of CAM 5.2 as an epithelial marker is assessed.

Topics: Antibodies, Monoclonal; Carcinoma; Histocytochemistry; Humans; Keratins; Melanoma; Sarcoma; Sarcoma, Synovial; Vimentin

One hundred cutaneous tumors were investigated immunohistopathologically for the expression of intermediate filament (IF) proteins. Epithelial tumors, such as basocellular and squamous cell carcinomas, cutaneous adnexal tumors, and metastatic carcinomas showed keratin positivity in a varying number of tumor cells with two keratin antibodies with different specificities. Neoplastic cells of fibrohistiocytic tumors, pigmented nevi, melanomas, hemangiomas, glomus tumors, and lymphomas were positive for vimentin, but not for keratin or desmin. Cutaneous leiomyomas and leiomyosarcomas, on the other hand, were positive for desmin. The results show that the typing of IFs enables the differential diagnosis between carcinomas and sarcomas or melanomas, epidermal appendage tumors, and mesenchymal tumors, and between fibrohistiocytic and leiomyocytic tumors, and therefore are of diagnostic value in histopathologic problems of the skin.

Topics: Adenocarcinoma; Adenoma, Sweat Gland; Antibodies, Monoclonal; Carcinoma, Adenoid Cystic; Carcinoma, Basal Cell; Carcinoma, Renal Cell; Carcinoma, Squamous Cell; Desmin; Diagnosis, Differential; Fluorescent Antibody Technique; Hemangioma; Histiocytoma, Benign Fibrous; Histocytochemistry; Humans; Intermediate Filament Proteins; Keratins; Leiomyoma; Melanoma; Neoplasm Metastasis; Nevus, Pigmented; Skin Neoplasms; Vimentin

Topics: Animals; Cell Line; Cells, Cultured; Drug Stability; HeLa Cells; Humans; Keratins; Melanoma; Mice; Neoplasms, Experimental; Retinoids

Topics: Antibodies, Monoclonal; Antibody Specificity; Antineoplastic Agents; Combined Modality Therapy; Debrisoquin; HLA Antigens; Humans; Hydroxylation; Keratins; Lymphatic Metastasis; Melanoma; Otorhinolaryngologic Neoplasms; Polymorphism, Genetic; Protease Inhibitors; Risk; Skin Neoplasms; Tumor Stem Cell Assay

Intermediate filament subunits in normal cells and in their malignant derivatives can be used as specific markers for their histogenetic origins. We have studied five neoplasms of the skin in which positive identification of vimentin containing intermediate filaments by indirect immunofluorescence microscopy helped to establish the diagnosis of malignant melanoma. All of the neoplasms included in this study posed problems in differential diagnosis by conventional light microscopy and yielded equivocal results by conventional histochemistry. Thus, definitive distinction between poorly differentiated carcinoma and poorly differentiated melanoma could not be made by conventional microscopy. In all of the neoplasms described here, immunolabeling with antibodies against different intermediate filaments demonstrated positive staining for vimentin only. This intermediate filament subunit is present in melanocytes (as well as in many mesenchymal cells) but not in epithelial cells. Our study indicates that this technique may be valuable in differential diagnosis of malignant melanoma, particularly in instances where cells lack melanin or show other atypical morphologic features.

Topics: Aged; Aged, 80 and over; Cell Nucleus; Cytoplasm; Desmin; Diagnosis, Differential; Female; Fluorescent Antibody Technique; Humans; Intermediate Filaments; Keratins; Male; Melanins; Melanoma; Middle Aged; Skin Neoplasms; Vimentin

A case of a malignant neoplasm with features suggestive of both malignant melanoma and squamous cell carcinoma is reported. The neoplastic cells were positive for both S-100 protein and keratin when stained by the indirect peroxidase-antiperoxidase method. The literature on other instances of bi- or multidirectional differentiation of neoplastic cells is reviewed. The significance of these findings for terminology of neoplasms is discussed.

Topics: Aged; Carcinoma, Squamous Cell; Facial Neoplasms; Female; Humans; Keratins; Melanoma; Neoplasms, Multiple Primary; S100 Proteins

Twenty-one anaplastic tumors were studied by light microscopy (LM), immunoperoxidase staining using anti-epidermal cytokeratin (ECK) and anti-Mallory body cytokeratin (MBCK) antibodies, and electron microscopy (EM), to determine whether an epithelial origin could be confirmed. The tumors were derived from lung, stomach, colon, breast, uterus, kidney, bladder, and mesothelium. By LM, the tumors consisted of either large and polygonal, spindle or small, round cells. With immunoperoxidase staining, 11 (52%) of the anaplastic tumors were positive for ECK, positivity being either absent or only weak in the main tumor mass, but marked in areas of infiltration and metastases. In contrast, all of the anaplastic tumors were positive for MBCK in the main tumor mass, infiltrating areas, and metastases. In the case of adenocarcinomas, staining was either web-like or diffuse throughout the cytoplasm with concentration occurring at the cell surface, whereas in mesotheliomas, the staining was either diffuse or showed focal perinuclear accentuation. Twelve of 13 anaplastic tumors examined by EM showed epithelial features (desmosomes, tonofilaments, lumina, and/or microvilli). As controls, 21 non-epithelial tumors (five melanomas, eight sarcomas, and eight lymphomas) showed no reactivity with either cytokeratin antibody. These studies show that the epithelial nature of undifferentiated and poorly differentiated tumors can be confirmed by immunohistochemistry using anti-cytokeratin antibodies.

Topics: Epithelium; Humans; Immunoenzyme Techniques; Keratins; Kidney Neoplasms; Lymphoma; Melanoma; Neoplasms; Sarcoma; Tissue Distribution

Twelve cases of malignant spindle-cell and sarcomatoid tumours of the skin of debatable nature were studied by immunocytochemical methods, using four antisera which might help contribute to resolution of the problems. The initial diagnosis made on structural grounds was confirmed by immunocytochemistry in six of eight cases in which a specific diagnosis had been made (one melanoma, three squamous carcinomas and two atypical fibroxanthomas). One case, initially regarded as AFX was reclassified as a squamous carcinoma, while a further case of possible AFX could not be confirmed by immunocytochemical study. Of the four cases in which structural examination was inconclusive, two were identified as squamous carcinomas and one as a melanoma by virtue of tumour markers. The fourth case was an intriguing actin-rich tumour of uncertain nature. Immunocytochemistry, despite certain limitations, has a valuable role to play in the analysis of the problematic spindle-cell malignant and pseudomalignant tumours of the skin.

Topics: Actins; Aged; Carcinoma, Squamous Cell; Female; Fibroma; Humans; Immunoenzyme Techniques; Keratins; Male; Melanoma; Middle Aged; Muramidase; S100 Proteins; Skin; Skin Neoplasms

Intermediate-sized filaments have been studied in human malignant melanomas and in normal melanocytes by immunofluorescence microscopy with antibodies directed against keratin, vimentin, desmin, neurofilament protein, and glial filament protein. Both human melanotic and amelanotic tumor cells and tumor metastases as well as normal melanocytes in human skin and in the rat eye contain exclusively intermediate filaments of the vimentin type. No reaction was seen with antibodies to keratin, desmin, neurofilaments, or glial filaments. These latter four antisera, however, gave strong reactions in epidermis and other epithelial tissues, muscle, or neural tissues, respectively. The results favor a mesenchymal character of melanocytes, although a neuroectodermal origin in an early developmental stage is possible. The finding that melanomas contain exclusively vimentin intermediate filaments may prove useful in differential diagnosis of melanomas from other tumor types.

Topics: Fluorescent Antibody Technique; Histocytochemistry; Humans; Intermediate Filament Proteins; Keratins; Melanoma; Neoplasm Proteins; Vimentin

Cell surface glycoconjugate patterns of human epidermal cells and of melanoma cells (MC) in primary culture derived from 11 primary and metastatic melanomas were investigated using fluorescent and horseradish peroxidase conjugated lectins for visualization at the light and electron microscopic level. The lectin labeling profiles of human melanocytes (M) and MC were found to be identical. According to their binding patterns, the lectins tested were grouped into three categories: (1) lectins binding to both keratinocytes (K) and M/MC, irrespective of neuraminidase pretreatment (concanavalin-A, wheatgerm agglutinin, succinylated wheatgerm agglutinin); (2) lectins binding to K but not to M/MC, irrespective of neuraminidase pretreatment (Ulex europaeus agglutinin I); (3) lectins binding to K, but to M/MC only after neuraminidase pretreatment (soybean, Helix pomatia, and peanut agglutinins). Untreated M were reactive for soybean and peanut agglutinins only at contact sites with K. Since the lectins from soybean, Helix, and peanut bind specifically to D-galactose and N-acetyl-D-galactosamine residues, we conclude that these particular glycoconjugates are normally masked by sialic acid on M/MC surfaces and can be unmasked by neuraminidase. These features, which have been previously observed in guinea pig M, appear to be interspecies surface markers of melanocytic cells which remain unaltered in the course of malignant transformation.

Topics: Animals; Concanavalin A; Epidermal Cells; Epidermis; Guinea Pigs; Humans; Immunologic Techniques; Keratins; Lectins; Melanins; Melanoma; Receptors, Mitogen; Wheat Germ Agglutinins

Six malignant melanomas have been examined for the type of intermediate filament they contain. All six cases showed positive staining of intermediate filaments with antibodies to vimentin, with cells containing large numbers of melanosomes being stained less strongly in general. The tumor cells did not react with antibodies to keratin, desmin, neurofilaments or glial fibrillary acidic protein. Thus typing of intermediate filaments can distinguish melanoma from undifferentiated carcinoma, but not from lymphoma or sarcoma. Since melanocytes are known to be vimentin positive, and since most of the samples we studied were from metastases, these results are a further indication that the intermediate filament type typical of the parental cell is retained in the metastases, as well as in the primaries of solid tumours. The implications of vimentin positivity for the histiogenesis of the melanocyte are also discussed.

Topics: Cytoskeleton; Desmin; Glial Fibrillary Acidic Protein; Histocytochemistry; Humans; Immunologic Techniques; Intermediate Filament Proteins; Keratins; Lymphatic Metastasis; Melanoma; Skin Neoplasms; Vimentin

The cytoskeletal intermediate filaments of pigmented nevi and malignant melanomas (nine cases of each) were evaluated using monospecific antibodies against intermediate filament proteins and immunofluorescence microscopy. Both pigmented nevi and cutaneous malignant melanomas showed only vimentin-type intermediate filaments, but not keratin, neurofilaments, desmin or glial fibrillary acidic protein. Thus, nevi and melanomas do not show neural characteristics in the cytoskeletal intermediate filament pattern although they appear to show other neural markers. Vimentin - content in melanomas versus keratin - content in carcinomas may be used as a differential diagnostic feature.

Topics: Desmin; Fluorescent Antibody Technique; Histocytochemistry; Humans; Intermediate Filament Proteins; Keratins; Melanoma; Neurofilament Proteins; Nevus, Pigmented; Skin Neoplasms; Vimentin

Determination of the type of intermediate filaments (IFs) present in a cell or tissue can yield information about its origin. Thus cells can be grouped into six different classes, i.e. epithelial cells characterized by cytokeratins, most but not all neurones characterized by neurofilaments (NFs), glial cells characterized by the presence of glial fibrillary acidic filaments, muscle cells characterized by the presence of desmin filaments, mesenchymal cells and certain other nonepithelial cell types characterized by the presence of vimentin, and other cells that appear not to contain IFs. The assignments made by immunologic techniques are supported by protein chemistry of the isolated proteins. Information derived from protein sequences as well as from DNA sequences establish that the major intermediate-filament proteins are different but related molecules and show also that the alpha-keratins of wool belong to this multigene family. Applications of IF typing to human pathologic material, and especially to the different major subgroups of human tumors, are reviewed. Thus, for instance, carcinomas continue to express cytokeratins, many tumors of neuronal origin express NFs, gliomas express glial fibrillary acidic protein (GFA), rhabdomyosarcomas express desmin, and nonmuscle sarcomas express vimentin. Further subclassification of epithelial cells and carcinomas is discussed. The subdivisions obtained by IF typing are striking because they follow well-known histologic principles; thus IF typing seems useful in certain instances where diagnosis is difficult by conventional techniques.

Topics: Animals; Cytoskeleton; Fluorescent Antibody Technique; Humans; Intermediate Filament Proteins; Keratins; Melanoma; Skin; Stomach Neoplasms; Vimentin

Topics: Adolescent; Cell Transformation, Neoplastic; Humans; Ichthyosis; Infant, Newborn; Keratins; Melanoma; Nevus; Nevus, Pigmented; Skin Neoplasms; Warts

Topics: Biopsy; Cell Membrane; Cytoplasm; Desmosomes; Humans; Keratins; Keratoderma, Palmoplantar; Melanoma; Microscopy, Electron; Skin; Skin Neoplasms

Topics: Adhesiveness; Bandages; Basement Membrane; Biopsy; Diagnosis, Differential; Dihydroxyphenylalanine; Humans; Keratins; Langerhans Cells; Male; Melanocytes; Melanoma; Microscopy, Electron; Middle Aged; Pigmentation Disorders; Skin Neoplasms; Vitiligo

Topics: Animals; Cell Line; Cytoplasmic Granules; Guinea Pigs; Keratins; Latex; Lysosomes; Melanins; Melanocytes; Melanoma; Mice; Mice, Inbred C57BL; Microscopy, Electron; Microspheres; Organoids; Phagocytosis; Pigmentation; Skin; Thorium Dioxide; Ultraviolet Rays