title: Impact of smoking status and cumulative smoking exposure on tumor recurrence of non-muscle-invasive bladder cancer.
abstract: OBJECTIVE
  To investigate the effect of smoking status, cumulative smoking exposure and smoking cessation on the outcomes of patient with non-muscle-invasive bladder cancer (NMIBC).
  
  
  METHODS
  We collected smoking data from 484 patients with NMIBC who were treated with transurethral resection (TUR); smoking status was categorized as (never smokers vs current smokers vs former smokers). Cumulative smoking exposure was categorized as high smoking exposure (cigarette index ≥400) versus low smoking exposure (cigarette index <400). Association with outcomes was examined by multivariable analyses after adjusting for the effects of standard clinicopathologic factors, and the Kaplan-Meier method was used to estimate the effect of smoking status and cumulative smoking exposure on RFS.
  
  
  RESULTS
  A total of 168 (34.7 %) patients were never smoker, 121 (25 %) patients were current smokers, and 195 (40.3 %) patients were former smokers. The median follow-up was 25 months. By multivariate analysis, pathological grade (p = 0.013), history of recurrence (p < 0.001), number of tumors (p < 0.001) and size of tumors (p = 0.013) were significantly associated with tumor recurrence; nevertheless, smoking status did not influence tumor recurrence (p = 0.063). Among current and former smokers, cumulative smoking exposure was significantly associated with tumor recurrence (p < 0.001), compared to current smokers, patients with smoking cessation ≥10 years had a lower risk of tumor recurrence [hazard ratio (HR) 0.456, p = 0.007].
  
  
  CONCLUSIONS
  Smoking affects the prognosis of patient with NMIBC, which is still controversial; however, among ever smokers, a high cumulative exposure smoking can significantly increase the risk of tumor recurrence. Quitting smoking might be associated with a lower recurrence rate for patients with NMIBC.
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Hao Min
authors.initials: HM
authors.lastname: Li
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Baihetiya
authors.initials: B
authors.lastname: Azhati
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Mulati
authors.initials: M
authors.lastname: Rexiati
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Wen Guang
authors.initials: WG
authors.lastname: Wang
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Xiao Dong
authors.initials: XD
authors.lastname: Li
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Urology, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Medical University, Xinjiang, 830054, People's Republic of China. wangyujie62@sina.com.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Wang
mesh_terms: D000368:Aged; D002295:Carcinoma, Transitional Cell / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*; D016540:Smoking Cessation; D013997:Time Factors; D047368:Tumor Burden; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000628:therapy
keywords: Cumulative exposure smoking; Non-muscle-invasive bladder cancer; Recurrence; Smoking status; Survival