Treatment of Dogs with Lymphoma Using a 12-week, Maintenance-Free Combination Chemotherapy Protocol

Abstract

Treatment of lymphoma in dogs by long-term chemotherapy has favorable results. However, the efficacy of short-term, maintenance-free treatment protocols on remission and survival times in dogs has not been determined. That treatment using a 12-week chemotherapy protocol would be associated with satisfactory treatment outcome in dogs with lymphoma. 77 dogs with histologically or cytologically confirmed diagnosis of lymphoma. Prospective clinical trial in which dogs were treated with a 12-week chemotherapy protocol consisting of L-asparaginase, vincristine, cyclophosphamide, doxorubicin, and prednisolone. Complete remission rate was 76.3%. Multivariate logistic regression analysis revealed that clinical substage (P = .006) and immunophenotype (P = .003) had a significant influence on the likelihood of a dog achieving complete remission. Median duration of first complete remission was 243 days (range 19-1,191 days). The 6-month, 1-year, and 2-year remission rates were 68%, 28%, and 16%, respectively. In the multivariate analysis of patient variables, immunophenotype (P = .022) revealed a significant influence on first remission duration. Toxicosis was mild with the exception of 1 treatment-associated death. In this group of dogs the 12-week maintenance-free chemotherapy protocol was well tolerated and had satisfactory results.