Blood Neutrophil‐to‐Lymphocyte Ratio as a Potential Prognostic Marker in Dogs ≤10 kg With Multicentric Lymphoma

Abstract

Canine lymphoma, the most prevalent haematopoietic tumour in dogs, presents significant challenges in veterinary oncology. This study investigates the prognostic value of the neutrophil‐to‐lymphocyte ratio (NLR) in small‐sized dogs (≤10 kg) with multicentric lymphoma. In this retrospective study, we examined medical records and haematological data from 35 dogs to assess the association between NLR and two key outcomes: time‐to‐progression (TTP) and lymphoma‐specific survival (LSS) using Cox proportional hazards models. Our findings revealed a significant correlation between elevated NLR and a worse prognosis, as evidenced by TTP (p = 0.005) and LSS (p = 0.001). NLR is linked to increased hazard ratios (HRs) for the time‐to‐progression rate (TTPR) at 180, 360 and 540 days (p = 0.001, p = 0.003 and p = 0.005, respectively) and the lymphoma‐specific survival rate (LSSR) at the same intervals (p = 0.016, p = 0.001 and p = 0.001, respectively). Cutoff value of 3.764 for NLR was established, above which there is a significantly increased risk of early disease progression and decreased survival. Additionally, our analysis indicates that dogs with substage b exhibited earlier progression than those with substage a, evident in overall (p = 0.026) and TTPR at 180 days (p = 0.004), 360 days (p = 0.018), 540 days (p = 0.026) and LSSR at 180 days (p = 0.033). The results underscore the potential of NLR as a prognostic marker in cases of dogs ≤10 kg with multicentric lymphoma, suggesting that higher NLR is associated with a poorer prognosis.