Evaluation of neutrophilia as a prognostic factor in dogs with multicentric lymphoma treated with a cyclophosphamide, doxorubicin, vincristine, and prednisone-based chemotherapy protocol.

Abstract

OBJECTIVE: To determine whether, in dogs with naïve multicentric lymphoma, neutrophilia at the time of initial diagnosis was associated with progression-free survival time (PFST) or overall response rate (ie, percentage of dogs with a complete or partial remission) and whether the initial neutrophil-to-lymphocyte ratio was associated with PFST. ANIMALS: 30 dogs with multicentric lymphoma and neutrophilia (including 16 treated with a cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP]-based protocol) and 37 historical control dogs without neutrophilia treated with a CHOP-based protocol. PROCEDURES: Medical records were reviewed, and PFSTs and responses were documented. RESULTS: Median PFST for the 16 dogs with neutrophilia treated with a CHOP-based protocol (70 days; range, 0 to 296 days) was significantly shorter than that for the 37 control dogs without neutrophilia (184.5 days; range, 23 to 503 days), and the overall response rate for dogs with neutrophilia (12/16 [75%]) was significantly lower than the rate for dogs without neutrophilia (36/37 [97%]). However, when all dogs in the study and control populations were considered together, the neutrophil-to-lymphocyte ratio at the time of diagnosis was not significantly associated with PFST. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that neutrophilia at the time of initial diagnosis may suggest a poorer prognosis in dogs with multicentric lymphoma. Prospective investigation into the role of neutrophils in the peripheral circulation and tumor microenvironment of cancer-bearing patients is warranted.