Geographic variations of predominantly hepatitis C virus associated male hepatocellular carcinoma townships in Taiwan: identification of potential high HCV endemic areas

Abstract

The proportion of B-HCC cases in Taiwan has progressively decreased over the last 20 years. It was not really due to an overall decrease in B-HCC but due to an increase in HCV-related HCC. The identification of potential HCV endemic areas in Taiwan has consequently become important. Data were collected retrospectively from eight Taiwan medical centers from 1981 to 2001, the geographical variations of male C-HCC townships in Taiwan were illustrated on maps. Goodness of fit was used to compare the anti-HCV prevalence in townships and cities, with the mean anti-HCV prevalence for Taiwan as a whole. Township-, city-, and county-specific prevalence of anti-HCV was presented as the median, ranges, and SMRs. Geographic variation can be analyzed in only 263 townships and cities. The maps were designed on the basis of different SMRs. The mean anti-HCV prevalence for male HCC patients in Taiwan was 31.9% (95% confidence interval: 30.7–33.0). Twenty-five townships distributed throughout central-western and south-western Taiwan have significantly higher prevalence (P < 0.05) (12 townships SMR ≥ 2; 13 townships 1.5 ≤ SMR < 2). Twenty-two townships have significantly lower prevalence (P < 0.05) (6 townships 0.5 ≤ SMR<1; 16 townships SMR < 0.5). Four different patterns of geographic variation in different counties were also noted and demonstrated. We successfully highlighted some potential high HCV endemic townships in Taiwan.