Clinical impact of lymphocyte/C-reactive protein ratio on postoperative outcomes in patients with rectal cancer who underwent curative resection.

Cancer-related systemic inflammation influences postoperative outcomes in cancer patients. Although the relationship between inflammation-related markers and postoperative outcomes have been investigated in many studies, their clinical significance remains to be elucidated in rectal cancer patients. We focused on the lymphocyte count/C-reactive protein ratio (LCR) and its usefulness in predicting short- and long-term outcomes after rectal cancer surgery. Patients with rectal cancer who underwent curative resection at our institution between 2010 and 2018 were enrolled in this study. We comprehensively compared the effectiveness of 11 inflammation-related markers, including LCR and other clinicopathological characteristics, in predicting postoperative complications and survival. Receiver operating characteristic curve analysis indicated that LCR had the highest area under the curve value for predicting the occurrence of postoperative complications. In the multivariate analysis, male sex (odds ratio [OR]: 2.21, 95% confidence interval [CI] 1.07-4.57, P = 0.031), low tumor location (OR: 2.44, 95% CI 1.23-4.88, P = 0.011), and low LCR (OR: 3.51, 95% CI 1.63-7.58, P = 0.001) were significantly and independently associated with the occurrence of postoperative complications. In addition, multivariate analysis using Cox's proportional hazard regression model for the prediction of survival showed that low LCR (≤ 12,600) was significantly associated with both poor overall survival (hazard ratio [HR]: 2.07, 95% CI 1.03-4.15, P = 0.041) and recurrence-free survival (HR: 2.21, 95% CI 1.22-4.01, P = 0.009). LCR is a useful marker for predicting both short- and long-term postoperative outcomes in rectal cancer patients who underwent curative surgery.