Despite the description of several new prognostic markers, colorectal cancer still represents the third most frequent cause of cancer-related death. As immunotherapy is considered a therapeutic alternative in such patients, neutrophil-to-lymphocyte (NLR) and lymphocyte-to-monocyte ratio (LMR) are hypothesized to provide reliable prognostic information. A retrospective study was conducted on 1052 patients operated on during 2013-2019 in two clinical hospitals from Hungary and Romania. Inclusion criteria targeted patients over 18 years old, diagnosed with rectal cancer, with preoperatively defined NLR and LMR. The overall survival rate, along with clinical and histopathological data, was evaluated. Overall survival was significantly associated with increased NLR (p = 0.03) and decreased LMR (p = 0.04), with cut-off values of 3.11 and 3.39, respectively. The two parameters were inversely correlated (p < 0.0001). There was no statistically significant association between tumor stage and NLR or LMR (p = 0.30, p = 0.06, respectively). The total mesorectal excision was especially obtained in cases with low NLR (p = 0.0005) and high LMR (p = 0.0009) values. A significant association was also seen between preoperative chemoradiotherapy and high NLR (p = 0.0001) and low LMR (p = 0.0001). In patients with rectal cancer, the preoperative values of NLR and LMR can be used as independent prognostic parameters. An NLR value of ≥3.11 can be used to indicate the response to preoperative chemoradiotherapy, but a low chance of sphincter preservation or obtaining a complete TME. Higher values of NLR and lower values of LMR require a more attentive preoperative evaluation of the mesorectum.
Keywords: lymphocyte-to-monocyte ratio; mesorectum; neutrophil-to-lymphocyte ratio; prognosis; rectal cancer; sphincter preserving.