The association of hepatitis B viral infection and hepatocellular carcinoma in New Zealand.

Eighty-eight patients presented to the Auckland hospitals with proven hepatocellular carcinoma between 1970 and 1981. The clinicopathological characteristics were analysed according to the racial and ethnic background of the patients. The cancer incidence for Auckland resident Polynesians (Pacific Islanders) was 5.8/100 000/year, that for the native Maori was 2.8/100 000/year and for the European was 0.6/100 000/year. The mean age in presentation of the hepatocellular carcinoma was 44, 49 and 63 years for Pacific Islanders, Maori and Europeans respectively. In general (non-tumorous) population, the hepatitis B surface antigen (HBSAg) carrier rate was 7.0% for the Pacific Islander and Maori and 0.5% for the Europeans. In the tumour patients where HBSAg were tested, 66% of Pacific Islanders, 100% of Maori and 0% of Europeans had positive antigenaemia. Histological sections were studied by orcein staining. Positive staining for viral particles were found mainly (80%) in hepatocytes of Pacific Island and/or Maori patients. These data indicated that within the same area, Pacific Islanders and Maori had a higher HBSAg carrier rate, higher incidence of hepatocellular carcinoma and presented at a younger age, and in the tumour-bearing patients had a higher incidence of HBSAg antigenaemia as well as viral particles in their liver.