title: Interaction between cigarette smoking and hepatitis B and C virus infection on the risk of liver cancer: a meta-analysis.
abstract: BACKGROUND
  Chronic infection with hepatitis B (HBV) and C viruses (HCV) as well as cigarette smoking are established risk factors of hepatocellular carcinoma (HCC), but it is unclear whether an interaction exists between these factors in causing hepatocellular carcinogenesis. We conducted a meta-analysis to evaluate the interaction of HBV and HCV infection and cigarette smoking on the risk of HCC.
  
  
  METHODS
  We systematically searched the PUBMED and the China National Knowledge Infrastructure databases. A total of 16 eligible publications were identified. Cigarette smoking and chronic HBV and HCV infections were dichotomized into present or absent. Additive (S) and multiplicative interaction indexes (V) between smoking and each of the two infections and their 95% confidence intervals (95% CI) were calculated for each study and then combined in a meta-analysis.
  
  
  RESULTS
  We found a more than additive interaction between HBV infection and cigarette smoking (S=1.44; 95% CI, 1.00-2.06; nine studies) and a more than multiplicative interaction (V=1.60; 95% CI, 1.16-2.20; six studies) between HCV infection and cigarette smoking. No publication bias was detected.
  
  
  CONCLUSIONS
  Smoking seems to interact with both HBV and HCV in determining HCC risk. A pooled analysis of individual subject data, with appropriate adjustment with other risk factors, is warranted to confirm these results.
  
  
  CONCLUSIONS
  The results of this study imply the evidence of a synergistic effect between smoking and HBV or HCV infection on the risk of HCC. Thus, chronic carriers of HBV or HCV are recommended to avoid smoking.
authors.affiliation: IARC, International Prevention Research Institute, 95 cours Lafayette, 69006 Lyon, France.
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Chuang
authors.forename: Yuan-Chin Amy
authors.initials: YC
authors.lastname: Lee
authors.forename: Mia
authors.initials: M
authors.lastname: Hashibe
authors.forename: Min
authors.initials: M
authors.lastname: Dai
authors.forename: Tongzhang
authors.initials: T
authors.lastname: Zheng
authors.forename: Paolo
authors.initials: P
authors.lastname: Boffetta
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000209:etiology* / Q000473:pathology; D016022:Case-Control Studies; D015331:Cohort Studies; D016174:Hepacivirus / Q000302:isolation & purification; D006509:Hepatitis B / Q000150:complications*; D006515:Hepatitis B virus / Q000302:isolation & purification; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D008113:Liver Neoplasms / Q000209:etiology* / Q000473:pathology; D012907:Smoking / Q000009:adverse effects*
references.citation: Cancer Causes Control. 2003 Apr;14(3):241-50
references.pmid: 12814203
references.citation: J Clin Gastroenterol. 1995 Apr;20(3):220-4
references.pmid: 7797831
references.citation: Am J Trop Med Hyg. 2002 Apr;66(4):389-93
references.pmid: 12164293
references.citation: Br J Cancer. 2007 Apr 10;96(7):1127-34
references.pmid: 17406349
references.citation: Cancer. 2004 Sep 1;101(5):1009-17
references.pmid: 15329910
references.citation: Am J Epidemiol. 2003 Apr 15;157(8):674-82
references.pmid: 12697571
references.citation: Cancer Res. 1991 Oct 15;51(20):5621-5
references.pmid: 1655259
references.citation: BMJ. 1997 Sep 13;315(7109):629-34
references.pmid: 9310563
references.citation: Int J Cancer. 1984 Dec 15;34(6):775-9
references.pmid: 6511124
references.citation: CA Cancer J Clin. 2005 Mar-Apr;55(2):74-108
references.pmid: 15761078
references.citation: Drug Metab Dispos. 1997 Feb;25(2):154-62
references.pmid: 9029045
references.citation: Am J Epidemiol. 1997 Jun 1;145(11):1039-47
references.pmid: 9169913
references.citation: Control Clin Trials. 1986 Sep;7(3):177-88
references.pmid: 3802833
references.citation: Int J Cancer. 1987 Jan 15;39(1):45-9
references.pmid: 3025110
references.citation: Int J Epidemiol. 2009 Dec;38(6):1497-511
references.pmid: 19720726
references.citation: Hepatology. 1999 Feb;29(2):328-33
references.pmid: 9918906
references.citation: Ann Ist Super Sanita. 1987;24(2):217-23
references.pmid: 3331068
references.citation: Cancer Res. 1982 Dec;42(12):5246-8
references.pmid: 6291750
references.citation: J Natl Cancer Inst. 2004 Dec 15;96(24):1851-6
references.pmid: 15601641
references.citation: Am J Epidemiol. 2002 Feb 15;155(4):323-31
references.pmid: 11836196
references.citation: Ann Intern Med. 2004 Mar 16;140(6):465-79
references.pmid: 15023713
references.citation: Hepatology. 2007 Feb;45(2):507-39
references.pmid: 17256718
references.citation: Eur J Clin Invest. 2006 Jul;36(7):459-65
references.pmid: 16796602
references.citation: IARC Monogr Eval Carcinog Risks Hum. 2004;83:1-1438
references.pmid: 15285078
references.citation: Int J Cancer. 2003 Oct 20;107(1):106-12
references.pmid: 12925964
references.citation: Am J Epidemiol. 2000 Jan 15;151(2):131-9
references.pmid: 10645815
references.citation: Psychoneuroendocrinology. 1998 Feb;23(2):189-204
references.pmid: 9621398
references.citation: Cancer Epidemiol Biomarkers Prev. 2009 Jul;18(7):2054-60
references.pmid: 19549812
references.citation: Int J Cancer. 1991 Sep 30;49(3):377-80
references.pmid: 1655659
references.citation: Cancer Epidemiol Biomarkers Prev. 2006 Apr;15(4):683-9
references.pmid: 16614109
references.citation: Int J Cancer. 2006 Jun 15;118(12):3030-44
references.pmid: 16404738
references.citation: BMC Nephrol. 2005 Nov 22;6:13
references.pmid: 16303055
references.citation: Jpn J Cancer Res. 1988 Oct;79(10):1075-82
references.pmid: 2848791
references.citation: Int J Cancer. 2008 Oct 15;123(8):1883-91
references.pmid: 18688864
references.citation: Gastroenterology. 2008 Jul;135(1):111-21
references.pmid: 18505690
references.citation: Br J Cancer. 2006 Mar 13;94(5):737-9
references.pmid: 16465190
references.citation: Am J Physiol Heart Circ Physiol. 2007 Jan;292(1):H76-82
references.pmid: 16920799
references.citation: Arch Intern Med. 2002 Apr 8;162(7):811-5
references.pmid: 11926856
references.citation: Hepatology. 1991 Mar;13(3):398-406
references.pmid: 1847891
references.citation: Cancer Lett. 2009 Dec 1;286(1):9-14
references.pmid: 19091458
references.citation: Lancet Oncol. 2007 Sep;8(9):773-83
references.pmid: 17714991
references.citation: Stat Methods Med Res. 2008 Apr;17(2):171-89
references.pmid: 17698938
references.citation: Natl Cancer Inst Monogr. 1985 Dec;69:213-5
references.pmid: 3834335
references.citation: BMJ. 2006 May 6;332(7549):1064-9
references.pmid: 16603565