Low baseline neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios predict increased overall survival in locally recurrent rectal cancer despite R1 margins.

Abstract

Prognostic features in locally recurrent rectal cancer (LRRC), beyond R0 surgery, are unknown. Aim of the present study was to evaluate the prognostic role of peripheral immune estimators, such as neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), on survival outcomes in LRRC patients. 184 LRRC patients treated at the National Cancer Institute of Milan (Italy) were included. Optimal cut-off values for NLR and PLR were determined. Kaplan-Meier curves and multivariate Cox analyses were used to assess the 5-yr overall survival (OS) according to NLR and PLR, also considering margins status. NLR >3.9 (hazard ratio [HR] 3.96, P=0.049), PLR >275 (HR 5.39, P = 0.002) and size on imaging (HR 1.36, P = 0.044) were associated to worse OS. R+ patients with NLR >3.9 showed a significantly lower 5-yr OS compared to NLR ≤3.9 (13.5% vs. 36.7%, P<0.0001). Also PLR >275 was related with a lower 5-yr OS compared to PLR ≤275 in R+ patients (6.4% vs. 36.8%, P = 0.0003). Conversely, NLR and PLR were irrelevant in case of R0 surgery. NLR and PLR predict 5-yr OS in LRRC, also identifying a subset of R+ patients with a similar expected survival compared to R0 cases.