A Nomogram Based on Platelet Distribution Width-to-Lymphocyte Ratio to Predict Overall Survival in Patients with Locoregionally Advanced Nasopharyngeal Carcinoma.

ABSTRACT

Purpose: To evaluate the prognostic significance of platelet distribution width-to-lymphocyte ratio (PDWLR) in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). Moreover, a nomogram based on PDWLR was built and validated to predict the overall survival (OS) of this population. Patients and Methods: All LA-NPC patients who were diagnosed and treated between January 2015 and December 2017 at Guangxi Medical University Cancer Hospital were included. Cox regression analyses were performed to assess PDWLR and clinical features that might affect OS to screen for independent predictors. The independent predictors and important clinical variables were used to build and validate a nomogram for predicting OS. Then, the capability of the model was estimated by discrimination, calibration and clinical usefulness. Risk stratification was conducted using the nomogram-calculated risk score, and the comparison of survival in the high-risk group and the low-risk group was through Kaplan-Meier method. Results: This study included 746 LA-NPC patients. Multivariate Cox analysis suggested that age (hazard ratio [HR] 1.81, 95% confidence interval [CI] 1.18-2.78, P = 0.007), gender (HR 2.03, 95% CI 1.12-3.68, P = 0.019), pre-treatment plasma Epstein-Barr virus (EBV) DNA (HR 1.55, 95% CI 1.01-2.39, P = 0.047), PDWLR (HR 2.61, 95% CI 1.67-4.09, P < 0.001) were independent predictors of OS. Compared to the 8th edition TNM staging system, the nomogram based on the above four factors and important clinical variables (T stage and N stage) demonstrated better predictive performance. Moreover, the model had the ability to identify individuals at high risk. Conclusion: PDWLR was a promising negative predictor for patients with LA-NPC. The nomogram based on PDWLR demonstrated better predictive performance than the current staging system.