mart-1-antigen and Adenocarcinoma

Topics: Adenocarcinoma; Adult; Biomarkers, Tumor; gp100 Melanoma Antigen; Humans; Immunoenzyme Techniques; Keratin-7; Male; MART-1 Antigen; Melanoma-Specific Antigens; Microphthalmia-Associated Transcription Factor; Retinal Neoplasms; Retinal Pigment Epithelium; S100 Proteins; Ultrasonography

Although a large number of immunohistochemical markers have been proven to be valuable in the differential diagnosis between epithelioid mesotheliomas and metastatic carcinomas involving the serosal membrane, no single antibody has been found that is absolutely sensitive and/or specific in making this distinction. A recent study reported melan A positivity in all 12 of the epithelioid mesotheliomas stained with a melan A antibody (clone A103). To fully determine the practical value of this antibody for assisting in the differential diagnosis of mesotheliomas, we investigated the expression of melan A (A103) in 40 mesotheliomas (27 epithelioid, 6 sarcomatoid, and 7 biphasic), 10 lung adenocarcinomas, and 10 serous carcinomas of the ovary. None of the mesotheliomas, lung adenocarcinomas, or serous carcinomas of the ovary were melan A (A103) positive. Similar staining results were observed in the 20 mesotheliomas immunostained in another institution using the same antibody clone from a different commercial source. On the basis of these results, it is concluded that in contrast to the initial report, melan A (A103) is not expressed in mesotheliomas and therefore, immunostaining with this antibody has no utility in the diagnosis of mesothelioma. The possible cause of the discrepancies between the results obtained in the present investigation and those of the initial study is discussed.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Biomarkers, Tumor; Cystadenocarcinoma, Serous; Diagnosis, Differential; Female; Gene Expression; Humans; Immunohistochemistry; Lung Neoplasms; MART-1 Antigen; Mesothelioma; Ovarian Neoplasms; Pleural Neoplasms; Retrospective Studies

Extra-mammary Paget disease (EMPD) is a rare intra-epithelial carcinoma that is usually found on the apocrine-rich skin of the perineum. We report 2 cases in which EMPD was initially misdiagnosed on the initial punch biopsy as melanoma-in-situ and Bowen disease respectively. Reasons for the misdiagnoses included a rare pigmented axillary variant of EMPD in the first case and atypical bowenoid features on H&E in the second. The cases are described with a critical review of the histopathological findings, along with a review of the current literature. This highlights the necessity of a comprehensive immunohistochemical panel for the assessment of intra-epithelial pagetoid atypical cells.

Topics: Adenocarcinoma; Aged; Biopsy; Bowen's Disease; Carcinoembryonic Antigen; Diagnostic Errors; Humans; Immunohistochemistry; Keratin-7; Male; MART-1 Antigen; Mohs Surgery; Mucins; Neoplasm Grading; Paget Disease, Extramammary; Prostate-Specific Antigen; Prostatic Neoplasms; Skin Neoplasms; Treatment Outcome

Myxoid variant of adrenocortical carcinomas (ACC) are rare, there being only 11 cases in the literature to date. Reported herein are the findings of a case, which in contrast to all previously reported myxoid ACC, was devoid of typical non-myxoid areas. The patient was a 61-year-old man in whom a left adrenal mass was detected during investigation of Cushing's syndrome. The adrenal was replaced by malignant cells and expanses of myxoid material. The cells were positive for melan-A, synaptophysin, vimentin and alpha-inhibin. The ultrastructural features of the cells were typical of adrenal cortical differentiation. The differential diagnosis of myxoid ACC includes extraskeletal myxoid chondrosarcoma, chordoma, myxoid adenocarcinoma, myxoma, lipomatous tumors, nerve sheath tumors, smooth muscle tumors, gastrointestinal stromal tumor and other sarcomas. The presence of myxoid material in a retroperitoneal lesion raises a broad differential diagnosis in which myxoid adrenocortical neoplasms should be included. Clinicoradiological correlation may be helpful, but special stains, immunohistochemistry and ultrastructural examination may be necessary to establish the diagnosis.

Topics: Adenocarcinoma; Adrenal Cortex Neoplasms; Adrenocortical Carcinoma; Antigens, Neoplasm; Chordoma; Diagnosis, Differential; Humans; Immunohistochemistry; Male; MART-1 Antigen; Microscopy, Electron; Middle Aged; Myxoma; Neoplasm Proteins; Nerve Sheath Neoplasms; Retroperitoneal Neoplasms; Synaptophysin; Vimentin

Androgen-independent prostate adenocarcinomas are responsible for about 6% of overall cancer deaths in men.. We used DNA microarrays to identify genes related to the transition between androgen-dependent and androgen-independent stages in the LuCaP 23.1 xenograft model of prostate adenocarcinoma. The expression of the proteins encoded by these genes was then assessed by immunohistochemistry on tissue microarrays (TMA) including human prostate carcinoma samples issued from 85 patients who had undergone radical prostatectomy.. FGFR1, TACC1 and WT1 gene expression levels were associated with the androgen-independent stage in xenografts and human prostate carcinoma samples. MART1 protein expression was correlated with pT2 tumor stages.. Our results suggest that each of these four genes may play a role, or at least reflect a stage of prostate carcinoma growth/development/progression.

Topics: Adenocarcinoma; Animals; Antigens, Neoplasm; Biomarkers, Tumor; Disease Progression; Fetal Proteins; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Male; MART-1 Antigen; Mice; Microtubule-Associated Proteins; Middle Aged; Models, Biological; Neoplasm Proteins; Neoplasm Staging; Nuclear Proteins; Oligonucleotide Array Sequence Analysis; Prostatic Neoplasms; Receptor, Fibroblast Growth Factor, Type 1; WT1 Proteins; Xenograft Model Antitumor Assays

Exosomes derived from tumours are small vesicles released in vitro by tumour cell lines in culture supernatants. To assess the role of these exosomes in vivo, we examined malignant effusions for their presence. We also investigated whether these exosomes could induce production of tumour-specific T cells when pulsed with dendritic cells.. We isolated exosomes by ultracentrifugation on sucrose and D(2)O gradients of 11 malignant effusions. We characterised exosomes with Western blot analyses, immunoelectron microscopy, and in-vitro stimulations of autologous T lymphocytes.. Malignant effusions accumulate high numbers of membrane vesicles that have a mean diameter of 80 nm (SD 30). These vesicles have antigen-presenting molecules (MHC class-I heat-shock proteins), tetraspanins (CD81), and tumour antigens (Her2/Neu, Mart1, TRP, gp100). These criteria, including their morphological characteristics, indicate the similarities between these vesicles and exosomes. Exosomes from patients with melanoma deliver Mart1 tumour antigens to dendritic cells derived from monocytes (MD-DCs) for cross presentation to clones of cytotoxic T lymphocytes specific to Mart1. In seven of nine patients with cancer, lymphocytes specific to the tumour could be efficiently expanded from peripheral blood cells by pulsing autologous MD-DCs with autologous ascitis exosomes. In one patient tested, we successfully expanded a restricted T-cell repertoire, which could not be recovered carcinomatosis nodules.. Exosomes derived from tumours accumulate in ascites from patients with cancer. Ascitis exosomes are a natural and new source of tumour-rejection antigens, opening up new avenues for immunisation against cancers.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Carcinoma; Cytoplasmic Vesicles; Dendritic Cells; Female; Humans; Male; MART-1 Antigen; Middle Aged; Neoplasm Proteins; Pleural Effusion, Malignant; Tumor Cells, Cultured