mart-1-antigen and Mouth-Neoplasms

Diagnostic records from 338 canine oral melanomas in 338 dogs received at the Veterinary Medical Diagnostic Laboratory (1992-1999) were reviewed. Of these tumors, 122 plus an additional 7 metastatic melanomas of unknown origin were selected for clinical follow-up, histologic review, and immunohistochemistry. Chow Chow, Golden Retriever, and Pekingese/Poodle mix breeds were overrepresented, whereas Boxer and German Shepherd breeds were underrepresented. There was no gender predisposition and the average age at presentation was 11.4 years. Forty-nine dogs were euthanized due to recurrence or metastasis. The average postsurgical survival time was 173 days. The gingiva and the labial mucosa were the most common sites. Most tumors were composed of either polygonal cells (27 cases, 20.9%), spindle cells (44 cases, 34.1%), or a mixture of the two (polygonal and spindle) (54 cases, 41.9%). Clear cell (3 cases, 2.3%) and adenoid/papillary (1 case, 0.8%) patterns were uncommon. The metastases of 6/6 oral melanomas had morphologic and immunohistochemical features similar to those of the primary tumors. Immunohistochemically, Melan A was detected in 113/122 oral (92.6%) and 5/7 (71.9%) metastatic melanomas. Only 4/163 nonmelanocytic tumors were focally and weakly positive for Melan A. Antibodies against vimentin, S100 protein, and neuron-specific enolase stained 129 (100%), 98 (76%), and 115 (89.1%) of 129 melanomas, respectively. Antibodies against other melanocytic-associated antigens (tyrosinase, glycoprotein 100) did not yield adequate staining. We conclude that Melan A is a specific and sensitive marker for canine melanomas.

Topics: Animals; Antigens, Neoplasm; Databases, Factual; Dog Diseases; Dogs; Female; Gingiva; Immunohistochemistry; Male; MART-1 Antigen; Melanoma; Mouth Neoplasms; Neoplasm Proteins; Retrospective Studies

Topics: Adult; Aged; Carcinoma, Squamous Cell; Epithelial Cells; Female; Follow-Up Studies; gp100 Melanoma Antigen; Humans; Keratins; Lymphatic Metastasis; Male; MART-1 Antigen; Melanins; Melanocytes; Melanoma-Specific Antigens; Middle Aged; Mouth Floor; Mouth Mucosa; Mouth Neoplasms; S100 Proteins; Tongue Neoplasms

The c-kit receptor is responsible for transmission of promigration signals to melanocytes; its downregulation may be involved in malignant progression of human melanocytic neoplasms. Expression of this receptor has not been examined in normal or neoplastic melanocytes from dogs. In this study, 14 benign dermal and 61 malignant mucosal melanocytic tumors were examined for c-kit (KIT) expression. Sites of the mucosal melanomas were gingiva (not further specified; n = 30), buccal gingiva (n = 6), soft palate (n = 4), hard palate (n = 5), tongue (n = 7), lip (n = 6), and conjunctiva (n = 3). Melan A was expressed in all 14 dermal melanocytomas and in 59 of 61 (96.7%) tumors from oral or conjunctival mucosa, confirming melanocytic origin. C-kit receptor expression was strong and diffuse throughout the cytoplasm in all 14 dermal melanocytomas and was identified in basilar mucosal melanocytes over submucosal neoplasms (27 of 61, 44.3%), junctional (neoplastic) melanocytes (17 of 61, 27.9%), and, less commonly, neoplastic melanocytes of the subepithelial tumors (6 of 61, 9.8%). KIT expression anywhere within the resected melanomas correlated with significantly longer survival. These results suggest that c-kit receptor expression may be altered in canine melanomas and may have potential as a prognostic indicator for mucosal melanomas.

Topics: Animals; Biomarkers, Tumor; Conjunctival Neoplasms; Disease Progression; Dog Diseases; Dogs; Female; Gene Expression Regulation, Neoplastic; Immunohistochemistry; Male; MART-1 Antigen; Melanocytes; Melanoma; Mouth Neoplasms; Prognosis; Proto-Oncogene Proteins c-kit; Receptor Protein-Tyrosine Kinases; S100 Proteins; Skin Neoplasms; Survival Analysis

The aim of this study was to analyze the histopathological and immunohistochemical characteristics of 22 cases of primary oral melanomas (OM).. Twenty two cases of primary oral melanoma were analyzed by description of their histopathological features and immunohistochemical study using the antibodies S-100, HMB-45, Melan-A and Ki-67.. The mean age was 58 years and 14 cases were female. The main affected sites were the hard palate, followed by the upper gingiva. Microscopically, 15 cases presented level III of invasion, 2 cases were amelanotic and 13 showed a mixed epithelioid and plasmacytoid or spindle cells composition. Some cases showed necrosis, perivascular and perineural invasion. S-100 and HMB-45 were positive in all cases, but 3 cases were negative for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 15.51% to 63% of positive cells.. S-100 and HMB-45 are more frequently expressed than Melan-A in primary oral melanomas and these markers are helpful to confirm the diagnosis.

Topics: Adult; Aged; Aged, 80 and over; Female; gp100 Melanoma Antigen; Humans; Immunohistochemistry; Ki-67 Antigen; Latin America; Male; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Middle Aged; Mouth Neoplasms; S100 Proteins; Young Adult

The balloon cell nevus is an uncommon variant of melanocytic nevi in which the majority of the proliferation consists of cells demonstrating peculiarly large clear, foamy, or finely vacuolated cytoplasm. The vacuolated cells represent altered nevus cells and upon immunoperoxidase evaluation react positively with several melanocytic markers. Complete excision results in cure. This report describes the second balloon cell nevus of the oral mucosa documented in the English-language literature.

Topics: Adult; Antigens, Neoplasm; Female; Humans; Immunoenzyme Techniques; MART-1 Antigen; Mouth Mucosa; Mouth Neoplasms; Neoplasm Proteins; Nevus, Pigmented; S100 Proteins

Primary mucosal melanomas (MMs) of the head and neck are a rare entity. Melanomas with characteristic melanin-pigmented tumor cells are easy to diagnose, but those without melanin-pigmented tumor cells, amelanotic melanomas, are difficult to identify and need immunohistochemistry (IHC) to confirm the final diagnosis. In this study, we examined the expression of three melanocytic differentiation markers, HMB-45, S-100, and Melan-A in primary oral and nasal MMs. We tried to evaluate whether HMB-45, S-100, and Melan-A were useful for diagnosis of primary oral and nasal MMs and to find out which marker was the best of the three.. This study used IHC to examine the expression of HMB-45, S-100, and Melan-A in 17 formalin-fixed paraffin-embedded specimens of primary oral and nasal MMs. The staining intensities (SIs) and labeling indices (LIs) of HMB-45, S-100, and Melan-A in 17 MMs were calculated and compared between any two markers.. Immunostaining results showed that the positive rate was 94% (16 of 17) for HMB-45, 88% (15 of 17) for S-100, and 71% (12 of 17) for Melan-A in 17 MMs. The SI of HMB-45 was significantly higher than that of S-100 (P = 0.0011) or of Melan-A (P = 0.0034). In addition, the mean LI of Melan-A (59 +/- 43%) was significantly lower than that of HMB-45 (83 +/- 28%, P = 0.0065) or of S-100 (79 +/- 33%, P = 0.0237).. Our results indicate that both HMB-45 and S-100 show a high positive rate and LI in MMs and therefore may be good markers for immunohistochemical diagnosis of primary oral and nasal MMs. In addition, HMB-45 may be a more sensitive marker than S-100 because HMB-45 shows a significantly higher SI than S-100 in this study.

Topics: Adult; Aged; Antigens, Neoplasm; Biomarkers, Tumor; Cell Nucleus; Coloring Agents; Cytoplasm; Female; Humans; Immunohistochemistry; Male; MART-1 Antigen; Melanocytes; Melanoma; Melanoma-Specific Antigens; Middle Aged; Mouth Mucosa; Mouth Neoplasms; Nasal Mucosa; Neoplasm Proteins; Nose Neoplasms; S100 Proteins; Sensitivity and Specificity

To develop a reverse transcriptase-polymerase chain reaction (RT-PCR) assay to detect canine melanoma-associated antigens (MAAs) and to use this technique to screen aspirates of lymph nodes (LNs) for evidence of metastatic spread of oral malignant melanoma.. 7 dogs with oral malignant melanoma and 4 dogs with multicentric lymphosarcoma.. We prepared cDNA from melanoma tumor biopsies and fine-needle aspirates obtained from submandibular LNs of dogs with oral malignant melanoma or multicentric lymphosarcoma. The RT-PCR assay was performed by use of tyrosinase, Melan-A, gp100, tyrosinase-related protein 2 (TRP-2), or melanoma antigen-encoding gene B (MAGE-B)-specific primers.. We detected MAGE-B mRNA in canine testicular tissue but not in melanoma biopsy specimens. Tyrosinase, Melan-A, gp100, and TRP-2 mRNAs were detected in tumor biopsy specimens and in 2 of 5 LN aspirates from dogs with melanoma, suggesting metastatic spread in those 2 dogs. We did not detect MAAs in LN aspirates obtained from dogs with multicentric lymphosarcoma. Sequencing of canine Melan-A and gp100 PCR products confirmed the specificity of the assay for these genes.. Clinical staging of dogs with oral malignant melanoma is useful to assist in designing appropriate treatments. However, results of histologic examination of LN biopsy specimens can be inconclusive and, in humans, can underestimate the number of patients with metastatic disease. Molecular staging of melanomas in dogs can be achieved by screening LN aspirates for MAA mRNA, and this can be performed in combination with cytologic examination to aid in detection of metastatic disease.

Topics: Animals; Antigens, Neoplasm; Base Sequence; Biomarkers; DNA, Complementary; Dog Diseases; Dogs; Female; Humans; Lymph Nodes; Lymphatic Metastasis; Male; MART-1 Antigen; Melanoma; Molecular Sequence Data; Mouth Neoplasms; Neoplasm Proteins; Polymerase Chain Reaction; RNA, Neoplasm; Testis

Mucosal melanomas of the oral cavity are rarely seen in the United States. The hard palate is the most common intraoral site. This unusual case occurred in the oral cavity of a 17-year-old Asian girl, who presented to her dentist with complaints of pain and swelling in the upper jaw. The lesion was distal and palatal to the maxillary left second molar, which was vital. Interestingly, the clinical presentation was a hyperplastic, tender lesion that bled when probed. Histopathologically, the biopsy demonstrated a sheet of spindle-shaped cells arranged in nests and fascicles. The nuclei were vesicular, oval to spindle-shaped, and some contained nucleoli that were distinguishable but not prominent. No melanin pigment was observed in the lesion. Tumor cells strongly expressed S100 protein, gp100 (HMB-45), and microphthalmia transcription factor, and variably expressed MART1, but not cytokeratins, CD34, or muscle-specific actin. The histopathologic features and immunohistochemical findings are consistent with a diagnosis of malignant melanoma.

Topics: Adolescent; Antigens, Neoplasm; Biomarkers, Tumor; DNA-Binding Proteins; Female; Humans; Immunohistochemistry; MART-1 Antigen; Melanoma; Melanoma-Specific Antigens; Microphthalmia-Associated Transcription Factor; Mouth Mucosa; Mouth Neoplasms; Neoplasm Proteins; S100 Proteins; Transcription Factors; Treatment Outcome

Malignant melanomas of the oral and sinonasal mucosa are rare tumors. Amelanotic variants can, on occasion, be difficult to recognize by routine light microscopy. Immunohistochemical studies may be needed for a final diagnosis. A number of new monoclonal antibodies to melanocytic differentiation antigens have been studied recently on primary cutaneous and metastatic melanoma. However, little is known about these antibodies for the diagnosis of mucosal melanomas. In this study the authors analyzed 79 oral and sinonasal mucosal melanomas of 65 patients. A total of 35 tumors originated from the oral mucosa (21 primary tumors, eight local recurrences, and six metastases) and 44 melanomas were from the sinonasal tract (27 primary tumors, nine local recurrences, and eight metastases). Immunohistochemical studies were performed on paraffin-embedded tissues, using the following antibodies: anti-S-100 protein, T311 (anti-tyrosinase), A103 (anti-Mart-1/Melan-A), D5 (antimicrophthalmia-associated transcription factor), and HMB-45 (anti-gp100). Of 35 oral mucosal tumors, 34 (97%) were positive with anti-S-100 protein, 33 (94%) with T311, 30 (85%) with A103, 26 (74%) with D5, and 25 (71%) with HMB-45. All five desmoplastic melanomas of the oral mucosa were positive for S-100 protein, four for tyrosinase, and one each for HMB-45 and A103. No desmoplastic melanoma was positive with D5. All 44 sinonasal melanomas were positive for tyrosinase and Mart-1/Melan-A (100%). Forty-three (98%) were positive with HMB-45, 42 (95%) with anti-S-100 protein, and 40 (91%) with D5. These results reveal that T311 is the most sensitive marker for sinonasal melanomas and closely approaches the sensitivity of anti-S-100 protein for oral mucosal melanomas. For desmoplastic mucosal tumors, anti-S-100 protein remains the most sensitive marker.

Topics: Antigens, Neoplasm; DNA-Binding Proteins; gp100 Melanoma Antigen; Humans; MART-1 Antigen; Melanocytes; Melanoma; Membrane Glycoproteins; Microphthalmia-Associated Transcription Factor; Monophenol Monooxygenase; Mouth Mucosa; Mouth Neoplasms; Nasal Mucosa; Neoplasm Proteins; Nose Neoplasms; S100 Proteins; Transcription Factors