[Correlation between preoperative inflammatory biomarkers and postoperative pneumonia or long-term prognosis in patients with esophageal cancer after neoadjuvant therapy]

Objective: To examine the correlation between neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR) and neutrophil-monocyte ratio (NMR) for postoperative pneumonia or long-term overall survival in patients with esophageal cancer after neoadjuvant therapy. Methods: The clinical data of 137 patients, including 111 males and 26 females, with the age of (M(Q_R))61(10) years (range: 45 to 75 years), undergoing radical resection of esophageal cancer after neoadjuvant therapy admitted at Department of Thoracic Surgery, West China Hospital from January 2016 to May 2019 were analyzed retrospectively. The blood routine one or two days before surgery and the occurrence of pneumonia after surgery were collected via hospital information system. The absolute count of neutrophils, lymphocytes and monocytes was recorded, to calculate NLR, LMR and NMR. The survival of patients was recorded systematically via follow-up. In the first part, the influencing factors of postoperative inflammation were analyzed, to group the patients into two groups according to the occurrence of postoperative pneumonia. χ² test, t-test or rank-sum test were conducted for inter-group comparison. In the second part, cutoff values of inflammatory biomarkers were obtained with the receiver operating characteristic (ROC) curve and grouped, with postoperative pneumonia as endpoint criteria. Independent factors correlated with postoperative pneumonia were determined through univariate and multivariate Logistic regression analysis. In the third part, the analysis on prognosis factors was carried on, with the survival as endpoint criteria. Cutoff values of inflammatory biomarkers were obtained with X-Tile software and grouped. The survival analysis was carried on with univariate and multivariate Cox proportional hazards regression model, and the Kaplan-Meier curve was drawn finally. The results of survival analysis were verified by Log-rank test. Results: Median follow-up time was 614 (299) days (range: 382 to 1 612 days). Cutoff values of NLR, LMR, and NMR obtained via the ROC curve were 3.0, 3.9, and 6.2, respectively. According to the multivariate Logistic regression analysis, NLR>3.0 (OR=2.740, 95% CI: 1.221 to 6.152, P=0.015) and LMR>3.9 (OR=0.140, 95% CI: 0.022 to 0.890, P=0.037) were independent prognosis factors for postoperative pneumonia in patients with esophageal cancer after neoadjuvant therapy. Cutoff values of NLR, LMR, and NMR obtained with X-Tile software were 3.3, 4.2, and 7.2, respectively. Through multivariate Cox proportional risk regression analysis, late tumor ypTNM staging (8th AJCC) (HR=2.087, 95% CI:1.079 to 4.038, P=0.029), poor pathologic response (HR=2.251, 95% CI: 1.117 to 4.538, P=0.023), and LMR>4.2 (HR=0.347, 95% CI: 0.127 to 0.946, P=0.039) could be independent prognosis factors for overall survival. Kaplan-Meier survival analysis indicated that the overall survival of patients with LMR ≤4.2 was worse (P=0.002), with the 1-year overall survival rate of 82.9%, and the 1-year overall survival rate of patients with LMR>4.2 was 94.6%. Conclusion: Preoperative LMR ≤3.9 and NLR>3.0 can be considered as independent prognosis factors for postoperative pneumonia, while LMR≤4.2 as one of independent prognosis factors for overall survival.