Monocyte and Lymphocyte Count, and Lymphocyte/Monocyte Ratio as Prognostic Factors at the Time of First Relapse in Canine Diffuse Large B-Cell Lymphoma Patients Receiving Chemotherapy

Abstract

Simple Summary Canine lymphomas account for the majority of haematopoietic tumours in veterinary clinical practice. Several prognostic factors have been evaluated in dogs with diffuse large B-cell lymphoma (DLBCL) and, more recently, the role of leukocytes has been of increased interest. The main objective of this study was to assess the prognostic value of absolute monocyte and lymphocyte count, as well as lymphocyte-to-monocyte ratio (LMR), at the time of first relapse in a population of dogs with diffuse large B-cell lymphoma treated with CEOP-based chemotherapy. Additionally, absolute monocyte and lymphocyte count, as well as LMR, were evaluated for their prognostic value at the time of diagnosis and throughout different timepoints during the course of the chemotherapy treatment. Monocyte counts, lymphocyte counts, and their ratio were not found to be significant predictors of overall survival at relapse or at the time of diagnosis in this population of dogs. Furthermore, our findings suggest that monitoring of the absolute lymphocyte count throughout chemotherapy treatment and during follow-up in these dogs may be of clinical help to identify disease progression. Larger, controlled prospective studies evaluating blood cell counts throughout the course of chemotherapy and at relapse are needed to evaluate these findings further.