A canine cutaneous lymphoproliferative disease resembling mycosis fungoides in man.

A dog with a lymphoproliferative disease resembling mycosis fungoides in man, the second reported canine case, had slowly progressive, multicentric cutaneous nodules and plaques. Nearly half the body surface was involved. The lesions consisted of multiple, flat, infiltrative, cutaneous tumors composed of heterogeneous, pleomorphic cells, some of which resembled histiocytes or activated lymphocytes. Intracutaneous foci of tumor cells and numerous tumor cells with bizarre convoluted nuclei were distinctive features that permitted the lesions to be distinguished from other non-epithelial cutaneous neoplasms.