title: The Gambia Liver Cancer Study: Infection with hepatitis B and C and the risk of hepatocellular carcinoma in West Africa.
abstract: Hepatocellular carcinoma (HCC) is the most common cancer in The Gambia. Hepatitis B virus (HBV) infection is endemic, with 15% to 20% of the population being chronic carriers, whereas hepatitis C virus (HCV) prevalence is low. We recruited 216 incident cases of HCC and 408 controls from three sites. HBV carriage was present in 61% (129/211) of HCC patients and 16% (64/402) of controls, whereas 19% (36/191) of HCC patients were HCV seropositive compared with 3% (11/382) of controls. HCC patients with HCV were notably older and were more likely to be female than those with HBV. Increased HCC risk was strongly associated with chronic HBV (odds ratio, 16.7; 95% CI, 9.7-28.7), HCV (16.7; 6.9-40.1), and dual infection (35.3; 3.9-323). We interpret the additive nature of risk with coinfection as representative of HBV and HCV acting primarily through shared steps in the multistage process of hepatocarcinogenesis. HCV infection was not observed among younger participants, suggesting a possible cohort effect. Reasons for the striking age and gender differences in HCC associated with HBV compared with HCV are unclear, but transmission patterns and age at exposure may be factors. In conclusion, in a standardized evaluation of well-characterized study participants from The Gambia, most cases of HCC are attributable to HBV (57%), but HCV adds a significant fraction (20%), especially among older patients and females. If HCV transmission is not perpetuated in future cohorts, focusing available resources on HB vaccination efforts could greatly ameliorate a major cause of cancer death in sub-Saharan Africa.
authors.affiliation: Viral Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, USA.
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Kirk
authors.forename: Olufunmilayo A
authors.initials: OA
authors.lastname: Lesi
authors.forename: Maimuna
authors.initials: M
authors.lastname: Mendy
authors.forename: Aliu O
authors.initials: AO
authors.lastname: Akano
authors.forename: Omar
authors.initials: O
authors.lastname: Sam
authors.forename: James J
authors.initials: JJ
authors.lastname: Goedert
authors.forename: Pierre
authors.initials: P
authors.lastname: Hainaut
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Hall
authors.forename: Hilton
authors.initials: H
authors.lastname: Whittle
authors.forename: Ruggero
authors.initials: R
authors.lastname: Montesano
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology*; D019353:Endemic Diseases; D005260:Female; D005714:Gambia / Q000453:epidemiology; D006509:Hepatitis B / Q000453:epidemiology*; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D017678:Sex Distribution