Use of Lomustine and Prednisolone as First-Line Treatment in Canine Multicentric Lymphoma.

Multiagent chemotherapy is considered the most effective treatment for canine high-grade lymphoma; however, due to cost and time requirements, single-agent protocols have also been described. The aim of our study was to evaluate the outcome and prognostic factors of dogs affected by multicentric lymphoma treated with lomustine and prednisolone as first-line treatment. Cases of medium-large-cell multicentric lymphoma treated with lomustine and prednisolone were included in the study. Response to therapy, time to progression (TTP), median disease-free interval (MDFI) and median survival time (MST) were retrospectively described. Thirty cases were included. Eleven (36.67%) were T cell, 11 (36.67%) were B cell and 8 (26.66%) had unknown immunophenotype. The overall response rate (RR) was 87%, with 15 patients achieving CR (50%) and 11 patients PR (37%). The median TTP, MDFI and MST were 42, 63 and 90 days, respectively. The only factor significantly associated with MDFI and MST was the stage. Dogs with multicentric lymphoma treated with lomustine and prednisolone have lower RR, TTP, MDFI and MST compared with dogs receiving multiagent protocols. Based on the short-lasting response, this study confirms that this protocol might have minimal utility beyond palliation.