EVALUATION OF MITOXANTRONE FOR THE TREATMENT OF LYMPHOMA IN DOGS

Mitoxantrone was administered to 74 dogs with lymphoma at a dosage of 5.0 mg/m(2) of body surface, IV, every 3 weeks. Thirty-four dogs had f ailed to respond to prior treatment with chemotherapeutic agents, whic h included doxorubicin (33 dogs). The remaining 40 dogs had not receiv ed prior treatment. Complete remission was determined in 19 of 74 dogs (26%), 10 of which had not received prior treatment. The median durat ion of remission for these 10 dogs was 94 days (range, 49 to 440 days, with 2 dogs still alive at 370 and 440 days, respectively). Nine dogs that had received prior treatment had complete remission that lasted for a median of 126 days (range, 42 to 792 days, with 1 dog still aliv e at 792 days). The combined remission rate (complete remission plus p artial remission) was 41%. Toxicosis was minimal, developing in only 9 dogs and requiring hospitalization of 2 dogs. We concluded that the c omplete remission rate ascertained when mitoxantrone was the only trea tment administered was low, compared with treatments that invoked othe r chemotherapeutic agents; however, the combined remission race of 41% indicated that mitoxantrone may be beneficial in the treatment oi lym phoma in dogs.