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

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 su rface antigen (HBsAg) and 37% for anti-HCV antibodies. To elucidate the aet iology of HCC and impact of HCV in this township, we conducted a case-contr ol study and compared HBV-related liver cancer mortality in Tzukuan and Tai wan 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 stu dy 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 HC C case. The HBsAg carrier rate was 40 . 7% in cases and 25 . 0% in controls (P = 0 . 1). And-HCV positive rate was 88 . 9% in cases and 53 . 7% in con trols (P = 0 . 008). Age-adjusted liver cancer mortality in Tzukuan (36 . 5 per 10(5)) was significantly higher than that of Taiwan as a whole (20 per 10(5)). Based on the HBsAg-positive rate among HCC patients (40 . 7% in Tz ukuan and 77 . 4-86 . 6% in Taiwan), the estimated HBV-related liver cancer mortality was similar in Tzukuan (14 . 9 per 10(5)) and Taiwan (15 . 8 - 1 7 . 3 per 10(5)). We concluded that HCV was the major risk factor for exces s liver cancer mortality in this HCV-endemic township of the HBV-endemic co untry.