Trends in incidence of hepatocellular carcinoma, 1990-2009, Khon Kaen, Thailand.

BACKGROUND: Liver cancer is the most frequent cancer among Thais especially people in northeastern Thailand, but there has as yet been no assessment of trend. The data of all cancers in Khon Kaen can be retrieved from data base of the Khon Kaen Cancer Registry (KKCR) which was established in 1984. OBJECTIVE: To assess the incidence trend of hepatocellular carcinoma in Khon Kaen, Thailand, between 1990 and 2009. METHODS: Population-based cases of liver cancer registered between 1985 and 2009 were retrieved from the KKCR data base and cases with diagnosis of hepatocellular carcinoma (HCC) with the coding C22.0 according to ICD-O were selected. Incidence trends were calculated using the Jointpoint analysis. RESULTS: There were 7,859 cases of HCC during the study period. Males were affected two times more frequently than females. The most common age group of cases was 50 and 69 years (60.3%). Most patients were diagnosed based on radiology imaging (40.6%) while the morphology verification was 7%. The age-standardized rates (ASR) were 13.1 to 49.8 per 100,000 among males and 4.8 to 38.4 per 100,000 among females depending on year of diagnosis since 1985. Remarkably, the ASRs were clearly low during first few years of starting the registration. The overall ASRs of HCC were 30.3 per 100,000 in males (95% CI: 25.9 to 34.6) and 13.1 per 100,000 (95% CI: 10.4 to 15.8) in females. During 1990-2009, the trends in incidences have been decreasing significantly with the annual percent change (APC) of 6.2% per year (95% CI: -7.6 to -4.8) in males and by 6.5% per year in females (95% CI: -8.4 to -4.9). CONCLUSIONS: The incidence trends have been decreasing in both sexes. The recent decline in incidence may represent a falling risk.

Trends in liver cancer incidence between 1985 and 2009, Khon Kaen, Thailand: cholangiocarcinoma.

BACKGROUND: The Khon Kaen Cancer Registry (KKCR), having both hospital and population-based registration, was established in 1984 at the Faculty of Medicine, Khon Kaen University. Liver cancer is the most frequent malignancy among Thais from northeastern Thailand, but there has hitherto been no assessment of trends over time. OBJECTIVE: To perform a statistical assessment of the incidence trends between 1985 and 2009 of liver cancer, specifically focusing on cholangiocarcinoma (CHCA). METHODS: Cases of CHCA, registered between 1985 and 2009, were retrieved from the KKCR and all those with a specific ICD-O-3rd diagnosis with a coding of C22.1, C24.0, C24.8 and C24.9 were selected. Incidence trends were calculated using the generalized linear model method (GLM), which generates incidence rate based logarithms. Jointpoint analysis was used to identify the best fitting model. RESULTS: Of the 18,589 cases of liver cancer 42% (7,859) were hepatocellular carcinoma and 58% (10,731) were CHCA. Among persons with CHCA, males were affected two times more frequently than females. Three-quarters of the cases were between 55 and 69 years of age. Morphology verified through a cytological or histological examination of tissue from the primary site (%MV) was only 10.8 % (1,141). The respective overall Age Standardized Rate (ASR) for CHCA from 1985 to 2009 was 16.8 to 62.0 per 100,000 among males and 4.8 to 25.6 per 100,000 among females. The respective, overall, ASR of CHCA among males vs. females was 44.3 per 100,000 (95% CI: 38.9 to 49.7) vs. 17.6 (95% CI: 14.5 to 20.7). Among males vs. females, the respective incidence from 1990 to 2009 has been significantly decreasing by -0.7% per year (Annual Percent Change, APC: -0.7%, 95%CI: -2.1% to +0.8%) vs. -0.4% per year (APC: -0.4%, 95% CI: -2.1% to +1.4%). CONCLUSIONS: The rate increase in the first 5 to 6 years may be due to improved completeness of the registry, since in the subsequent 10 to 12 years there is a rather stable rate. It may be, however, that the recent decline in incidence represents a real fall in risk.