Excess mortality from hepatocellular carcinoma in an HCV-endemic township of an HBV-endemic country (Taiwan).

Abstract

Taiwan is an endemic area of hepatitis B virus (HBV). All previous studies have concluded that HBV is the major cause of hepatocellular carcinoma (HCC) in Taiwan. An HBV- and hepatitis C virus (HCV)-endemic township, Tzukuan, in southern Taiwan has been identified with the prevalence of 24% for HB surface antigen (HBsAg) and 37% for anti-HCV antibodies. To elucidate the aetiology of HCC and impact of HCV in this township, we conducted a case-control study and compared HBV-related liver cancer mortality in Tzukuan and Taiwan as a whole. Based on cancer registration datasets of 2 medical centres from 1991 to 1995, we recruited 18 male and 9 female HCC cases from the study township. Their mean age (±standard deviation) was 60·3 (± 7.3) years. Randomly sampled from a community-based survey, 4 age- (± 2 years) and sex-matched residents were selected as community controls for each HCC case. The HBsAg carrier rate was 40·7% in cases and 25·0% in controls (P = 0·1). Anti-HCV positive rate was 88·9% in cases and 53·7% in controls (P = 0·008). Age-adjusted liver cancer mortality in Tzukuan (36·5 per 10⁵) was significantly higher than that of Taiwan as a whole (20 per 10⁵). Based on the HBsAg-positive rate among HCC patients (40·7% in Tzukuan and 77·4–86·6% in Taiwan), the estimated HBV-related liver cancer mortality was similar in Tzukuan (14·9 per 10⁵) and Taiwan (15·8–17·3 per 10⁵). We concluded that HCV was the major risk factor for excess liver cancer mortality in this HCV-endemic township of the HBV-endemic country.