title: Pretreatment platelet-to-lymphocyte ratio (PLR) as a predictor of response to first-line platinum-based chemotherapy and prognosis for patients with non-small cell lung cancer.
abstract: BACKGROUND
  Previous studies showed the platelet-to-lymphocyte ratio (PLR) was associated with the prognosis of many tumors. However, to our knowledge, no study has explained the role of PLR in predicting response to first-line chemotherapy and prognosis for patients with non-small cell lung cancer (NSCLC). The aim of this study was to characterize the role of pretreatment PLR in NSCLC.
  
  
  METHODS
  We consecutively enrolled 210 patients who were diagnosed with NSCLC in Jinling hospital (Nanjing, China) between January 2001 and August 2012. The platelet and lymphocyte counts of peripheral blood were measured before treatment was initiated. Each patient received at least two cycles of standardized combination chemotherapy. The response to chemotherapy was assessed after two cycles.
  
  
  RESULTS
  Based on a receiver operator characteristic (ROC) curve, 152.6 was defined as the cut-off value of PLR for predicting response. An evaluated PLR (≥152.6) was an independent risk factor for response to first-line chemotherapy [odds ratio (OR), 4.503; 95% confidence interval (CI): 2.213-9.166, P=0.000]. Univariate and multivariate survival analyses showed that an elevated PLR was associated with a poor prognosis for patients with NSCLC [hazard ratio (HR), 1.867; 95% CI: 1.328-2.625; HR, 2.025; 95% CI: 1.405-2.919, respectively].
  
  
  CONCLUSIONS
  Our study shows that PLR maybe a potentially useful biomarker for predicting response to first-line chemotherapy and prognosis in NSCLC.
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Hongbing
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Zhaofeng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Yanwen
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Chen
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: He
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Yunfen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Song
keywords: Non-small cell lung cancer (NSCLC); platelet to lymphocyte ratio; prognosis; response