Lymphocyte-monocyte ratio as a predictive marker for pathological complete response to neoadjuvant therapy in esophageal squamous cell carcinoma

Background: The hematological markers of systemic inflammation has been proved to be significantly associated with clinical outcomes in esophageal cancer. This retrospectively study was to evaluate the value of the hematological markers in predicting pathological complete response (pCR) and overall survival (OS) in patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC) who received neoadjuvant chemoradiotherapy (nCRT). Methods: A total of 87 patients with newly diagnosed LA-ESCC were retrospectively analyzed. The pretreatment lymphocyte-monocyte ratio (LMR), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) were selected as hematological markers. Results: After nCRT, 26 (29.9%) patients achieved pCR and 61 (70.1%) patients had non-pCR. The LMR was significantly higher in patients who achieved pCR compared to that in patients who did not achieve pCR (4.35 +/- 1.68 vs. 3.33 +/- 1.13, P=0.002). Based on the receiver operating characteristic (ROC) curve, the optimal cut off value of LMR that predicted pCR was 3.73 [area under the curve: 0.712; 95% confidence interval (CI): 0.594-0.830; P=0.002], with a sensitivity of 65.4% and specificity of 77.0%. The pCR rate of patients with LMR >= 3.73 was 53.1%, while the pCR rate of patients with LMR <3.73 was only 16.4% (P<0.001). The univariate and multivariate logistic regression analysis confirmed that LMR was an independent predictor of pCR [odds ratio: 5.093; 95% CI: 1.658-15.646; P=0.004]. However, in the prediction of OS, a multivariate Cox proportional hazard model revealed that only clinical stage [hazard ratio (HR): 1.970; 95% CI: 1.144-3.391; P=0.014] and pCR (HR: 0.469; 95% CI: 0.237-0.928; P=0.030) were independent prognostic factors. Conclusions: Pre-treatment LMR may predict pCR in LA-ESCC patients who were treated with nCRT. Having pCR is an independent prognostic factor for prolonged survival.