Feline-type cystic basal cell tumor filled with abundant melanin pigment-rich fluid in a dog

• Published in: Journal of Veterinary Medical Science Vol. 81; no. 2; pp. 269 - 273
• Main Authors: LEE, Seoung-Woo, JI, Hoon, BAEK, Su-Min, LEE, A-Rang, KIM, Min-Ji, PARK, Sang-Joon, CHOI, Seong-Kyoon, YUN, Sungho, KIM, Tae-Hwan, JEONG, Kyu-Shik, PARK, Jin-Kyu
• Format: Journal Article
• Language: English
• Published: Japan JAPANESE SOCIETY OF VETERINARY SCIENCE 2019; Japan Science and Technology Agency; The Japanese Society of Veterinary Science
• Subjects: basal cell tumor; CD34 antigen; dark fluid; Degeneration; dog; feline; Melanin; Pathology; Skin; dark fluid; feline; dog; basal cell tumor; melanin
• ISSN: 0916-7250; 1347-7439
• DOI: 10.1292/jvms.18-0277

A 2-year-old castrated male mongrel dog presented with a well-demarcated fluctuant dermal mass, located on the back of the neck. Grossly along with cystic structures filled with a black greasy fluid, when cut open. Microscopically, the mass was multi-lobulated. The lobules consisted of neoplastic basaloid cells and showed central degeneration, forming multiple central cystic structures filled with dark melanin-pigmented materials. Immunohistochemically, the neoplastic cells were strongly positive for CK14 and partially positive for CK19, but negative for CK7, CK8/18, CD34, S-100, Melan-A and α-SMA. Based on the findings, the present case was diagnosed as a feline-type basal cell tumor characterized by cystic structures filled with abundant black fluid.