title: Cigarette smoking increases the risk of mortality from liver cancer: A clinical-based cohort and meta-analysis.
abstract: OBJECTIVE
  Although the influence of cigarette smoking on the incident risk of liver cancer has been determined, the association between smoking and liver cancer mortality remains uncertain.
  
  
  METHODS
  We searched Pubmed, EmBase, and Web of Science databases to obtain eligible studies. Hazard ratio (HR) value and 95% confidential intervals (CI) were pooled by using a random-effects model, and dose-response analyses were conducted to quantify associations between smoking and mortality from liver cancer.
  
  
  RESULTS
  A total of 27 articles involving four million participants from seven countries by retrieval (published 1986-2014) were finally included. Pooled HR values for liver cancer mortality was 1.45 (95% CI: 1.33-1.59), 1.22 (95% CI: 1.11-1.34) and 1.16 (95% CI: 1.01-1.32) for current, former, and ever smokers, respectively, when compared with nonsmokers. The risk increased by 7.1% (95% CI: 1.4-13.2) for per additional 10 cigarettes per day and by 5.2% (95% CI: 0.02-11.2) for per additional 10 pack-years. In our population recruiting 597 patients with liver cancer, smoking status was further identified as a significant determinant factor of tumor size and serum level of gamma-glutamyl transpeptidase, but not a significant prognostic factor.
  
  
  CONCLUSIONS
  Cigarette smoking, especially current smoking, significantly increased mortality risk from liver cancer.
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Pang
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Qu
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Jingyao
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Xinsen
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Sushun
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Sidong
authors.initials: S
authors.lastname: Song
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Ruitao
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Lingqiang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Hepatobiliary Surgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood; D002423:Cause of Death; D015331:Cohort Studies; D016001:Confidence Intervals; D016206:Databases, Bibliographic; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000097:blood / Q000401:mortality* / Q000473:pathology; D016016:Proportional Hazards Models; D012306:Risk; D012907:Smoking / Q000009:adverse effects*; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D014408:Biomarkers, Tumor; D005723:gamma-Glutamyltransferase
keywords: epidemiology; liver cancer; meta-analysis; mortality; smoking