Source Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center. 5-1-1 Tsukiji Chuo-ku Tokyo 104-0045 Japan.
BACKGROUND & AIMS: Fish is a rich source of n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA). Although consumption of fish and n-3 PUFA has been reported to protect against development of some types of cancer, little is known about its association with hepatocellular carcinoma (HCC).
METHODS: We investigated the association between fish and n-3 PUFA consumption and HCC incidence (n=398) in a population-based prospective cohort study of 90,296 Japanese subjects (45-74 years old). Hazard ratios (HRs) and 95% confidence intervals (CIs) for the highest vs the lowest quintile were estimated from multivariable adjusted Cox proportional hazards regression models. We also conducted subanalyses of subjects with known hepatitis B or C virus (HBV or HCV) status, and of subjects that were anti-HCV and/or HB surface antigen (HBsAg)-positive. All tests of statistical significance were 2-sided.
RESULTS: Among all subjects, consumption of n-3 PUFA-rich fish and individual n-3 PUFAs was inversely associated with HCC, in a dose-dependent manner. HRs for the highest vs lowest quintiles were 0.64 (95% CI, 0.42-0.96) for n-3 PUFA-rich fish, 0.56 (95% CI, 0.36-0.85) for EPA, 0.64 (95% CI, 0.41-0.98) for DPA, and 0.56 (95% CI, 0.35-0.87) for DHA. These inverse associations were similar irrespective of HCV or HBV status.
CONCLUSION: Consumption of n-3 PUFA-rich fish or n-3 PUFAs, particularly of EPA, DPA and DHA, appears to protect against development of HCC, even among subjects with HBV and/or HCV infection.