The incidence of hepatocellular carcinoma in New Zealand

Aim. To measure the incidence rate of hepatocellular carcinoma (HCC) in New Zealand, by ethnicity, sex, region and age. Methods. Cancer Registry data for 1983-94 were used to calculate rates of p rimary liver cancer (ICD code 155.0) and HCC (both ICD code 155.0 and ICD-O morphology code 8170) directly standardised to Segi's world population and standardised for region. Results. Rates of HCC per 100 000 person years 6.6 and 1.3 for Maori males and females, 14.7 and 4.6 for Pacific people, and 0.8 and 0.3 for Other (in clusive of Chinese). The rates for Chinese for 1989-94 were 19.9 and 5.8. T hese rates are likely to be underestimates due to imperfect sensitivity of ICD-O code 8170 registrations for HCC. The rates of HCC far Maori and Pacif ic people (sexes combined) were 7.3 and 18.0 times that for other for 1983- 94; the HCC rate for Chinese was 25.8 times greater than Europeans for 1989 -94. Rates of HCC tended to be higher in the north of New Zealand, compared to the south, for Maori and Other/ Europeans, but there was no apparent re gional gradient for Pacific people and Chinese. Conclusions. Non-Europeans have higher rates of HCC than Europeans due to v ariations in hepatitis B carriage. Males have higher rales than females, an d Maori and Europeans living in the north of New Zealand have higher rates of HCC than those living in the south. It is estimated that any hepatitis B screening and follow-up programme will detect one incident case of RCC per year per 2000 hepatitis B carriers in the target population, or one incide nt case per 1000 carriers actually participating in regular follow-up.