High-grade B-cell lymphoma of the penis in a cat.

perineal urethrostomy. Histopathology confirmed a high-grade B-cell lymphoma confined to the penis and extending microscopically to the prepuce. The cat remained disease free for 6 mo before dying of an unknown cause. To the authors' knowledge, this case may represent the first reported instance of a feline lymphoma clinically confined to the penis. Key clinical message: Penile lymphoma, though rare in cats, should be considered in the differential diagnosis for perineal or penile masses. Surgical excision can achieve local control, but prognosis and the role of adjuvant therapy remain uncertain.