Decreasing trend of esophageal adenocarcinoma in Hong Kong.

Background: The incidence of esophageal adenocarcinoma was increasing in the Western Europe and United States, but not in East Asian countries. Population based study on the trend of esophageal adenocarcinoma in Hong Kong was not available. Materials and Methods: Population-based data of Hong Kong Cancer Registry from 1984 to 2003 were used. Cases were grouped into four 5-year periods. Average age standardized rate (WSR) of each period was calculated by averaging the WSR of the 5 years in each period, basing on the world standard population, with adjustment made for cases with missing histology. Results: 10,751 new cases of esophageal neoplasm were studied (8,637 males and 2,114 females). Esophageal adenocarcinoma declined among both males and females, with the total number decreased from 224 in 1984 to 1988 to 131 in 1998 to 2003. WSR decreased from 1.10 of 100,000 in 1984 to 1988 to 0.34 of 100,000 in 1998 to 2003. The decline was faster than that for esophageal squamous cell carcinoma so that the relative ratio of esophageal adenocarcinoma decreased from 11.7% in 1984 to 1988 to 6.4% in 1998 to 2003. Conclusions: The incidence of esophageal adenocarcinoma and ratio of esophageal adenocarcinoma versus esophageal squamous cell carcinoma decreased in Hong Kong.