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. The
present 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 was
removed by surgical excision under local anaesthesia. The mass had a dry, dark and blackish cut surface. Cytological evaluation
revealed 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 cytoplasm
obscuring the nuclear details. Junctional activity and intra-epidermal nesting of neoplastic cells were noticed. Blood vessels and
connective tissue stroma were evident amidst the neoplastic melanocytes. Bleached tissue sections revealed numerous spindle
and round cells with mild or no cytoplasmic pigmentation. Nucleus was large and round with multiple nucleoli arranged near
to nuclear membrane. Based on the gross and histopathological findings, the current case was diagnosed as congential cutaneous
malignant melanoma.