title: Pretreatment platelet count improves the prognostic performance of the TNM staging system and aids in planning therapeutic regimens for nasopharyngeal carcinoma: a single-institutional study of 2,626 patients.
abstract: BACKGROUND
  Thrombocytosis has been identified as an unfavorable prognostic factor in several types of cancer. This study aimed to evaluate the prognostic value of pretreatment platelet count in association with the TNM staging system and therapeutic regimens in patients with nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  A total of 2,626 patients with NPC were retrospectively analyzed. Platelet count >300 × 10(9)/L was defined as thrombocytosis. Matched-pair analysis was performed between patients receiving chemoradiotherapy and radiotherapy.
  
  
  RESULTS
  Multivariate analysis showed that platelet count was an independent unfavorable prognostic factor for overall survival (OS) [hazard ratio (HR) = 1.810, 95% confidence interval (CI) = 1.531-2.140, P < 0.001] and distant metastasis-free survival (DMFS) (HR = 1.873, 95% CI = 1.475-2.379, P < 0.001) in the entire patient cohort. Further subgroup analysis revealed that increased platelet count was an independent unfavorable prognostic factor for OS and DMFS in patients with NPC stratified by early and advanced T category, N category, or TNM classification (all P ≤ 0.001). Receiver operating characteristic (ROC) curves verified that the predictive value of TNM classification for OS was improved when combined with pretreatment platelet count (P = 0.030). Matched-pair analysis showed that chemoradiotherapy significantly improved OS only in advanced-stage NPC with thrombocytosis (HR = 0.416, 95% CI = 0.226-0.765, P = 0.005).
  
  
  CONCLUSIONS
  Pretreatment platelet count, when combined with TNM classification, is a useful indicator for metastasis and survival in patients with NPC. It may improve the predictive value of the TNM classification and help to identify patients likely to benefit from more aggressive therapeutic regimens.
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 420720927@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 420720927@qq.com.
authors.forename: Yu-Pei
authors.initials: YP
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. zhaobch@mail2.sysu.edu.cn.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. zhaobch@mail2.sysu.edu.cn.
authors.forename: Bing-Cheng
authors.initials: BC
authors.lastname: Zhao
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 379408685@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 379408685@qq.com.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 63122634@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 63122634@qq.com.
authors.forename: Lu-Jun
authors.initials: LJ
authors.lastname: Shen
authors.affiliation: Department of Radiation Oncology, Anhui Provincial Hospital, Hefei, Anhui, 230001, PR China. gj1166@sina.com.
authors.forename: Jin
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 837460199@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 837460199@qq.com.
authors.forename: Zhuo-Yao
authors.initials: ZY
authors.lastname: Mai
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 1241062108@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 1241062108@qq.com.
authors.forename: Meng-Kun
authors.initials: MK
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. halokenneth@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. halokenneth@qq.com.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. 464648912@qq.com.|Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 464648912@qq.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Yan
authors.affiliation: Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, PR China. 1297622324@qq.com.
authors.forename: Su
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine; Sun Yat-sen University Cancer Center, Guangzhou, Guangdong, 510060, PR China. xiayf@sysucc.org.cn.|Department of Radiation Oncology, Sun Yat-sen University Cancer Center, 651 Dongfeng Road East, Guangzhou, Guangdong, 510060, PR China. xiayf@sysucc.org.cn.
authors.forename: Yun-Fei
authors.initials: YF
authors.lastname: Xia
mesh_terms: D002277:Carcinoma; D059248:Chemoradiotherapy; D006801:Humans; D015999:Multivariate Analysis; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms; D009367:Neoplasm Staging; D010976:Platelet Count; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D013922:Thrombocytosis