Systemic immune-inflammation index predicts the clinical outcome in patients with nasopharyngeal carcinoma: a propensity score-matched analysis

// Wenjie Jiang 1, * , Yuan Chen 1, * , Jin Huang 1 , Dan Xi 1 , Jun Chen 2 , Yingjie Shao 1 , Guoping Xu 1 , Wenming Ying 1 , Jun Wei 1 , Junjun Chen 1 , Zhonghua Ning 1 , Wendong Gu 1 and Honglei Pei 1 1 Department of Radiation Oncology, The Third Affiliated Hospital of Soochow University, Changzhou 213003, P.R. China 2 Department of Respiratory, The Seventh People’s Hospital of Changzhou, Changzhou 213000, P.R. China * These authors have contributed equally to this work Correspondence to: Zhonghua Ning, email: nzh96086@163.com Wendong Gu, email: hony0428@126.com Honglei Pei, email: hongleipei@126.com Keywords: SII, nasopharyngeal carcinoma, prognosis, PSM Received: April 12, 2017 Accepted: June 28, 2017 Published: August 02, 2017 ABSTRACT Systemic immune-inflammation index (SII), based on peripheral lymphocyte, neutrophil, and platelet counts, was recently investigated as a prognostic marker in several tumors. However, SII has not been reported in nasopharyngeal carcinoma (NPC). We evaluated the prognostic value of the SII in 327 patients with NPC. Univariate and multivariate analyses were calculated by the Cox proportional hazards regression model. The time-dependent receiver operating characteristics (ROC) curve was used to compare the discrimination ability for OS. PSM (propensity score matching) was carried out to imbalance the baseline characteristics. Our results showed that SII, PLR, NLR and MLR were all associated with OS in NPC patients in the Kaplan-Meier survival analysis. SII (HR: 2.26; 95% CI: 1.40-3.66; P=0.001), NLR (HR: 1.66; 95% CI: 1.08-2.53; P=0.020), and MLR (HR: 1.99; 95% CI: 1.17-3.39; P=0.011) were identified to be the independent prognostic factors. The AUC for SII was bigger than NLR, PLR and MLR for predicting survival in patients with NPC in 3 or 5-years. In the PSM analysis, SII remained an independent predictor for OS in NPC patients (HR=2.08, CI 1.22-3.55, P=0.007). SII is a novel, simple and inexpensive prognostic predictor for patients with NPC. The prognostic value of SII is superior to PLR, NLR and MLR.