Patterns of familial transmission of HBV and the risk of developing liver cancer: a case-control study in the Philippines.

The present case-control study was carried out in the Philippines to determine the risk of developing hepatocellular carcinoma (HCC) in relation to different HBV serological profiles of parents and sibs of HCC cases and controls. The HBV serological profiles of parents and sibs of 33 patients with HCC were compared with those of 2 types of community control: 33 general population controls matched for sex and age (C1 controls) and 33 asymptomatic HBsAg carriers also matched for sex and age (C2 controls). When cases were compared with C1 controls, increased risks were associated with the fact of having an HBsAg-positive mother (RR = 2.5, 95% C1 = 0.4-26.3) and older sibs positive for HBsAg (RR = 2.0, 95% C1 = 0.5-9.1), but the increased risk was not statistically significant. However, a significantly increased risk was associated with the fact of having a mother (95% C1 = 3.5-infinity) or father (RR = 11, 95% C1 = 1.6-473) who had been exposed to HBV. On the other hand, when cases were compared with C2 controls, a non-significant 2-fold increase was associated with the fact of having an HBsAg-positive mother, but no differences were observed in the HBV serological profiles of their fathers and older sibs. These results suggest that, in the Philippines, the fact of having a mother or father who has been infected in the past with HBV increases the risk of developing HCC but that the contribution of the mother to this increase in risk is not as important as hitherto believed.