title: Hepatitis B virus status and the risk of pancreatic cancer: a meta-analysis.
abstract: OBJECTIVE
  Whether hepatitis B virus (HBV) infection increases the risk of pancreatic cancer (PaC) is controversial. We carried out a meta-analysis to evaluate the association between HBV status and the risk of PaC.
  
  
  METHODS
  PubMed, Embase, and the China National Knowledge Infrastructure were searched from their inception through April 2012 for case-control and cohort studies that have reported an association between HBV status and the risk of PaC. The reference lists of pertinent publications were also reviewed for potential studies. Methodological quality was assessed using the Newcastle-Ottawa Quality Assessment Scale. A random-effects model was used to summarize odd ratios (ORs) and 95% confidence intervals (CIs).
  
  
  RESULTS
  We included seven case-control studies and three cohort studies, involving 5883 PaC cases. The summary OR of developing PaC was 1.22 (95% CI: 0.90-1.67) for individuals who were HBV surface antigen (HBsAg)-positive. Compared with the individuals who were never exposed to HBV infection, the summary OR of the risk of PaC was 1.60 (95% CI: 1.26-2.05) for chronic or inactive HBsAg carriers (HBsAg-positive) and 1.76 (95% CI: 1.05-2.93) for anti-HBc-positive but anti-HBs-negative individuals.
  
  
  CONCLUSIONS
  Inactive HBsAg carrier status and possible occult HBV infection may increase the risk of PaC. Large population-based multicenter prospective studies are required to further confirm this finding.
authors.affiliation: Department of Social Medicine and Health Management, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Wang
authors.forename: Shengli
authors.initials: S
authors.lastname: Yang
authors.forename: Fujian
authors.initials: F
authors.lastname: Song
authors.forename: Shiyi
authors.initials: S
authors.lastname: Cao
authors.forename: Xiaoxv
authors.initials: X
authors.lastname: Yin
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Tu
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.forename: Xing
authors.initials: X
authors.lastname: Xu
authors.forename: Xiaoxin
authors.initials: X
authors.lastname: Dong
authors.forename: Zuxun
authors.initials: Z
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D006509:Hepatitis B / Q000150:complications*; D006510:Hepatitis B Antibodies / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006513:Hepatitis B e Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000737:chemistry*; D006801:Humans; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000209:etiology*; D012307:Risk Factors
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens