Cutaneous melanocytoma associated with vitiligo and leukotrichia in a mixed‐breed pig

A 7-month-old, male castrated mixed-breed pig presented for evaluation of a 3-month history of cutaneous pigmented nodular lesions, multifocal leukoderma and leukotrichia. Skin biopsies were performed from pigmented nodules and depigmented skin for histopathology. Additional skin biopsies were collected aseptically for bacterial and fungal tissue cultures. Histopathologic diagnosis was a benign melanocytic neoplasm (melanocytoma) and marked vitiligo. Spontaneous regression of melanocytomas did not occur after 1 year of age as previously reported to occur in several swine breeds. Topical imidazoquinoline amine cream was applied to one melanocytoma three times a week for a month. No clinical improvement in either the melanocytoma or vitiligo occurred. In humans, vitiligo is associated with both neoplastic and benign melanocytic neoplasms; this case illustrates the presence of melanoma-associated leukoderma in a domestic mixed-breed pig and emphasises the importance of meticulous skin examination in swine patients with the development of vitiligo.