Systemic inflammation-based predictors of pathological response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer patients

To investigate whether systemic inflammation-based predictors can predict tumor response to neoadjuvant chemoradiotherapy (CRT) in patients with locally advanced rectal cancer (LARC).Totally, 205 LARC patients undergoing neoadjuvant CRT and curative surgery between 2008 and 2017 were analyzed. After propensity score matching, 132 patients were included in the study. Hematological parameters were collected, and their relationship with tumor response was investigated.After propensity score matching, patients in good response group before CRT displayed significantly lower neutrophil-lymphocyte-ratio (NLR) and platelet-lymphocyte-ratio (PLR) than those in poor response group, while there were no significant differences in all hematological characteristics between the two groups after CRT. The cutoff values of pre-CRT NLR and pre-CRT PLR after receiver operating characteristic analysis were 3.10 and 198.7, respectively. Multivariate analysis revealed that while there was no association between pre-CRT PLR and tumor response, pre-CRT NLR ≥3.1 was identified as the predictor of poor tumor response (P = 0.007).An increased NLR before CRT can serve as a hematological factor for predicting a poor tumor response in LARC.