Congenital melanoma in a crossbred Jersey calf – A case report

Abstract

Congenital melanocytic tumors are rather frequently occurring neoplasms in domestic animals especially in bovines. Thepresent paper document a condition of congenital cutaneous melanoma in a 3 days old crossbred Jersey calf. Clinically, a large,firm, irregularly round growth measuring about 20X17cms was noticed on the right lateral side of the neck. The tumour mass wasremoved by surgical excision under local anaesthesia. The mass had a dry, dark and blackish cut surface. Cytological evaluationrevealed few individual cells with blackish-brown cytoplasmic pigments. Histopathologically, round to fusiform neoplastic melanocytes were noticed proliferating in the dermis. Abundant brownish-black melanin pigments were noticed in the cytoplasmobscuring the nuclear details. Junctional activity and intra-epidermal nesting of neoplastic cells were noticed. Blood vessels andconnective tissue stroma were evident amidst the neoplastic melanocytes. Bleached tissue sections revealed numerous spindleand round cells with mild or no cytoplasmic pigmentation. Nucleus was large and round with multiple nucleoli arranged nearto nuclear membrane. Based on the gross and histopathological findings, the current case was diagnosed as congential cutaneousmalignant melanoma.