Cutaneous epitheliotropic lymphoma in a ferret.

An 8-year-old spayed female ferret was examined for diffuse generalized alopecia, erythema, erosions, crusts, and ulcerated plaques that were nonresponsive to long-term administration of corticosteroids. Cutaneous epitheliotropic lymphoma was diagnosed on the basis of histologic examination of skin biopsy specimens. Neoplastic cells were determined to be of T-lymphocytic origin by results of immunohistochemical staining with a rabbit anti-CD3 monoclonal antibody. Additional laboratory abnormalities detected included anemia, azotemia, isosthenuria, pyuria, and bacteriuria. Treatment included isotretinoin and amoxicillin trihydrate plus clavulanate potassium administered orally, and oatmeal-based shampoos. Isotretinoin was tolerated well and cutaneous lesions resolved after 60 days of treatment, but pretreatment azotemia worsened and the ferret was euthanatized. Necropsy revealed cutaneous epitheliotropic lymphoma, pyelonephritis, and interstitial nephritis. Renal disease most likely was caused by immunosuppression secondary to chronic treatment with corticosteroids and aging. Isotretinoin, although not curative, may be useful for the palliative treatment of cutaneous epitheliotropic lymphoma in ferrets.