Evidence for clustering of hepatitis B virus infection in families of patients with primary hepatocellular carcinoma.

Family member of 13 patients with hepatitis B surface antigen (HBsAg) positive primary hepatocellular carcinoma (PHC) were tested for the presence of hepatitis B virus-associated antigens and antibodies. Of the 122 members examined, circulating HGsAg was detected in 47 (39%), antibody to HBsAg (anti-HBs) was found in 37 (30%), and antibody to hepatitis B core antigen (anti-HBc) alone was present in 13 (11%). The relatives with the highest frequency of HBsAg positivity were the offspring of the propositus, followed by the nieces and nephews and the grandchildren. Anti-HBs and anti-HBc were detected most often in the spouses and non-blood relatives. Evidence for past and present hepatitis B virus (HBV) infection was more frequently found in the Asian family members when compared to the non-Asians. The e antigen (HBeAg) was present in 38% of the HBsAg positive individuals, including four with PHC; antibody to HBcAg (anti-HBe) was rarely detected. These results indicate that clustering of HBV infection was commonly present in family members of patients with PHC. The HBsAg positive individuals may be major contributors to the endemic pool of the virus, and may themselves be potential cases of chronic active type B hepatitis, cirrhosis, and PHC.