Prognostic Value of Sarcopenia and Systemic Inflammation Markers in Patients Undergoing Definitive Radiotherapy for Esophageal Cancer

Objective: To determine the independent and combined prognostic value of sarcopenia and systemic inflammatory markers in esophageal cancer patients undergoing definitive radiotherapy. Methods: Sarcopenia was diagnosed on the basis of the skeletal muscle index (SMI) as determined by the skeletal muscle area at the third lumbar (L3) region and body height. The optimal cutoff value of systemic inflammatory markers was determined by the receiver-operating curve (ROC). Logistic regression was used to analyze the correlation among different variables. Cox proportional hazards model was used to identify the factors significantly correlated to overall survival (OS). Based on the results of multivariate survival analysis, a nomogram was established to predict the survival rate. The accuracy of the nomogram was evaluated by the coordination index and the calibration curve. Results: A total of 100 esophageal cancer patients were included, of which 77 exhibited sarcopenia. The lymphocyte-monocyte ratio (LMR) was significantly correlated to the risk of sarcopenia (OR = 0.637, 95% CI, 0.452-0.898, P = 0.010). In addition, sarcopenia (P = 0.002, HR = 3.991, 95% CI: 1.653-9.638) and LMR < 2.67 (P < 0.001, HR = 2.665, 95% CI: 1.563-4.543) were independent predictors of OS. Two nomograms with good predictive accuracy were established. Conclusion: Sarcopenia and LMR can independently predict the survival of patients with esophageal cancer receiving definitive radiotherapy and have good combined prognostic value.