mart-1-antigen and Cat-Diseases

Topics: Animals; Antigens, Neoplasm; Biomarkers, Tumor; Cat Diseases; Cats; Lymphocytes, Tumor-Infiltrating; MART-1 Antigen; Melanoma; Retrospective Studies; Skin Neoplasms

Nonocular melanocytic neoplasia is considered uncommon in cats yet is routinely encountered in diagnostic pathology and recognized to exhibit a wide variation in biological behavior. Accurate prediction of clinical outcomes is challenging with no widely recognized prognostic criteria. Signalment and tumor location were retrospectively evaluated in 324 cats diagnosed with nonocular melanocytic neoplasia. Histologic features were described in 141 neoplasms and outcome data were available in 79 cases. Immunohistochemistry using Melan-A, PNL-2, cyclooxygenase 2 (COX-2), and E-cadherin was performed in a subset (

Topics: Animals; Biomarkers, Tumor; Cat Diseases; Cats; Female; Immunohistochemistry; Male; MART-1 Antigen; Melanocytes; Mitosis; Necrosis; Neoplasm Grading; Neoplasms; Prognosis; Retrospective Studies; Sensitivity and Specificity

Immunohistochemistry, using a monoclonal antibody to Melan A and a polyclonal antibody to S100 protein, was applied to 48 formalin-fixed, paraffin-embedded specimens of feline melanoma. Forty-two cutaneous, three oral, one mucocutaneous, and two metastatic melanomas comprised the tumors. Thirty-two tumors (67%) were positive for Melan A and 42 (87.5%) were positive for S100. All but one of the tumors that were positive for Melan A were also positive for S100. S100 was detected in 11 of 16 tumors that were negative for Melan A. Seventy-five percent (9 of 12) of amelanotic melanomas were negative for Melan A. Normal adrenal cortex, the cerebellum, and the skin had cells that were positive for Melan A. Sebaceous adenoma was the only nonmelanocytic tumor examined that reacted with antibody to Melan A. Although less sensitive than S100 protein, Melan A is more specific for melanoma and is useful in differentiating feline cutaneous melanoma from the more common pigmented basal cell tumor.

Topics: Animals; Antigens, Neoplasm; Cat Diseases; Cats; Immunohistochemistry; MART-1 Antigen; Melanoma; Neoplasm Proteins; S100 Proteins; Skin; Skin Neoplasms