title: Melan A and S100 protein immunohistochemistry in feline melanomas: 48 cases.
abstract: 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.
authors.affiliation: Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri, Columbia 65205, USA. ramosj@missouri.edu
authors.forename: J A
authors.initials: JA
authors.lastname: Ramos-Vara
authors.forename: M A
authors.initials: MA
authors.lastname: Miller
authors.forename: G C
authors.initials: GC
authors.lastname: Johnson
authors.forename: S E
authors.initials: SE
authors.lastname: Turnquist
authors.forename: J M
authors.initials: JM
authors.lastname: Kreeger
authors.forename: G L
authors.initials: GL
authors.lastname: Watson
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000032:analysis; D002371:Cat Diseases / Q000473:pathology*; D002415:Cats; D007150:Immunohistochemistry; D058965:MART-1 Antigen; D008545:Melanoma / Q000145:classification / Q000473:pathology / Q000662:veterinary*; D009363:Neoplasm Proteins / Q000032:analysis*; D009418:S100 Proteins / Q000032:analysis*; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000145:classification / Q000473:pathology / Q000662:veterinary*
chemical_list: D000951:Antigens, Neoplasm; D058965:MART-1 Antigen; D009363:Neoplasm Proteins; D009418:S100 Proteins