Interaction of benzo[a]pyrene with other risk factors in hepatocellular carcinoma: a case-control study in Xiamen, China

Purpose: Large epidemiologic studies about the relationship between benzo[a]pyrene (B[a]P) and hepatocellular carcinoma (HCC) have been limited. B[a]P diol epoxide (BPDE) is a highly reactive metabolite of B[a]P that binds covalently to form DNA adducts. We evaluated the interaction between B[a]P exposure with other risk factors in HCC, in a case-control study of 345 HCC and 961 healthy controls. Methods: Concentration of BPDE-DNA adducts in blood was determined by enzyme-linked immunosorbent assay. The interaction between BPDE-DNA adducts and other risk factors on HCC were evaluated by multivariate logistic regression analysis. Results: Mean concentration of BPDE-DNA adducts in blood of cases was significantly higher than that of the controls. The risk of HCC increased with elevated concentration of BPDE-DNA adducts (x(2) = 203.57, P-trend < .001) and the odds ratio was 7.44 (95% confidence interval, 5.29-10.45) for the first versus fourth quartile of adduct levels. The relative excess risk due to interaction between BPDE-DNA adducts and hepatitis B virus surface antigen and drinking was 34.71 and 54.92, and the attributable proportion due to interaction was 41.53% and 75.59%, respectively. Conclusions: The high level of BPDE-DNA adducts in blood is associated with HCC and that environmental exposure to B[a]P may increase the risk of HCC, especially among drinkers and populations with hepatitis B virus infection. (C) 2014 Elsevier Inc. All rights reserved.