Vinblastine as a second rescue for the treatment of canine multicentric lymphoma in 39 cases (2005 to 2014)

Abstract

OBJECTIVES: The objective of this study was to retrospectively evaluate response and outcome of dogs with multicentric lymphoma treated with single-agent vinblastine as a second rescue. METHODS: Medical records from 39 client-owned dogs receiving vinblastine rescue treatment (having relapsed on or following completion of UW-Madison and CCNU/L-asparaginase protocols), between 2005 and 2014, were reviewed for information regarding clinical presentation, diagnostic testing, drug dosage, number of treatments, side effects, response and outcome. RESULTS: The median starting dose of vinblastine was 2·6 mg/m(2) (1·7 to 2·8 mg/m(2) ), administered weekly until disease progression. Of the 39 dogs treated, 3 dogs (7·7%) achieved a complete remission, 7 dogs (17·9%) achieved a partial response, 18 dogs (46·2%) maintained stable disease and 11 (28·2%) had progressive disease. Ten dogs (25·6%) developed a grade III or IV neutropenia, and 4 dogs (10·3%) developed grade III or IV thrombocytopenia (one dog in both categories). After starting vinblastine, the median progression-free survival was 29·5 days (0 to 77 days) and overall median survival time was 46 days (4 to 250 days). Duration of first remission was identified as a positive predictor of outcome. CLINICAL SIGNIFICANCE: Single-agent vinblastine is well tolerated in dogs with relapsed or refractory lymphoma. Responses were incomplete and short-lasting.