Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio Predict Survival in Rectal Cancer Patients Receiving Neoadjuvant Concurrent Chemoradiotherapy

Abstract

Background This study investigated the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in rectal cancer patients receiving neoadjuvant concurrent chemoradiotherapy (CCRT) Methods One hundred and eighty-four patients with newly-diagnosed rectal cancer receiving neoadjuvant CCRT were enrolled between January 2006 and December 2016 Pre-CCRT NLR and Pre-CCRT PLR were determined based on complete blood count obtained within two weeks before neoadjuvant CCRT The cut-off values were set by two different methods: the mean value and the maximum of Youden's index Overall survival (OS) and disease-free survival (DFS) between patients with high and low NLR and PLR were compared using the Kaplan-Meier method and log-rank tests We performed univariate and multivariate Cox proportional hazard models controlling for age gender grade perineural invasion (PNI) lymphovascular invasion (LVI) circumferential resection margin (CRM) post-neoadjuvant pathological (yp) stage and tumor regression grade (TRG) Stratified survival analyses by yp stage were also conducted Results The mean follow-up time was 72 73 ±36 82 months The cut-off values of pre-CCRT NLR and PLR by using the mean value were 3 5 and 188 respectively The cut-off values of pre-CCRT NLR and PLR by using the maximum of Youden's index were 2 6 and 112 2 respectively Patients with NLR >3 5 and >2 6 had statistically significantly worse DFS (p= 011; p= 005) and OS (p= 016; p= 038) compared with patients with NLR ?3 5 and ?2 6 respectively PLR >188 and >112 2 patients possessed statistically significantly inferior DFS (p= 011; p= 039) but not OS (p= 185; p= 281) compared with PLR patients ?188 and ?122 2 respectively Multivariate analyses revealed worse DFS (adjusted HR [aHR]=2 8 95%CI: 1 473-5 419 p= 002; aHR=1 769 95%CI: 1 130-2 771 p= 013) and OS (aHR=1 871 95%CI: 1 029-3 4 p= 04; aHR=1 584; 95%CI: 1 035-2 425; p= 034) in the NLR >3 5 and >2 6 groups after adjusting for covariates After adjustments the PLR >188 and >112 2 groups had inferior DFS (aHR=2 274 95%CI: 1 047-4 937 p= 038; aHR=1 667 95%CI: 1 263-2 014 p= 038) but not OS Further stratified analysis by yp stage indicated that only yp stage II and III patients with NLR >3 5 and >2 6 had worse DFS (aHR=2 334 95% CI: 1 158-4 725 p= 018; aHR=1 719 95% CI: 1 170–2 526 p= 006) and OS (aHR=2 226 95% CI: 1 165-4 251 p= 015; aHR=1 552 95%CI: 1 021–2 361 p= 040) Additionally only yp stage II and III patients with PLR >188 and >112 2 had inferior DFS (aHR=2 012 95% CI: 1 049-3 861 p= 036; aHR=1 645 95%CI: 1 019–2 655 p= 042) Conclusions Elevated pre-CCRT NLR patients had inferior DFS and OS and high pre-CCRT PLR patients had worse DFS but not OS; the results were similar under two methods of cut-off values Pre-CCRT NLR seemed to be better than PLR as the predictors for pathological complete response (pCR) Therefore the study suggested that elevated pre-CCRT NLR might be better than PLR as an independent prognostic factor for poor survival outcome in rectal cancer patients and could be used to identify high-risk patients for more intense treatment and care

Date of Award	2020
Original language	English
Supervisor	Yu-Wen Chien (Supervisor)