Esophageal cancer mortality trends during the last 30 years in high risk areas in China: comparison of results from national death surveys conducted in the 1970's, 1990's and 2004-2005.

BACKGROUND AND AIMS

China was one of the countries with the highest esophagus cancer (EC) mortality in the world during the 1970's. This report provides data on time trends of esophagus cancer mortality during the 1970's-21st century in high risk areas, considering the remarkable geographic variation of EC mortality in China. The aim was to explore changing trends of EC mortality during past 30 years, and provide basic information on prevention and control of EC in high risk areas in China.

METHODS

Among the high risk areas of EC defined in the 1970's, ten that have joined in all the three death causes sampling surveys were selected in this study. Subjects included all cases dying from esophageal cancer in these sites during 1973-1975, 1990-1992, and 2004-2005. The EC mortality data and relevant demographic data of ten areas covered by all the three surveys were extracted from the national death causes survey database.

RESULTS

Compared with the EC mortality of the ten high risk areas in the 1970's, the crude mortality rates (CMR) in the 1990's reduced by 0.04%47.3%, and the CMRs in the early 21st century decreased by 9.25%62.0% from the 1990's; the age specific mortality rate adjusted by China standard population (ASMRc) in the 1990's reduced by 8.22%53.5%, and the ASWRc in the early 21st century decreased by 25.0%78.0% from the 1990's; the age-specific mortality rates adjusted by world standard population (ASMRw) in the 1990's reduced by 7.54%51.9%, and the ASMRw in the early 21st century decreased by 24.5%79.2% from the 1990's; the proportional mortality ratios (PMR) in the 1990's reduced by 12.3%41.3%, and the PMRs in the early 21st century decreased by 6.76%52.6% from the 1990's.

CONCLUSION

Our study indicated that the mortality of esophageal cancer in high risk areas of China had declined after three decades, but still remained high compared with the national level. Esophageal cancer is still a major cancer burden in high risk areas. It is necessary to further promote the prevention and control program of esophageal cancer in these areas of China.