Marked Variations in Colon Cancer Epidemiology: Sex-specific and Race/Ethnicity-specific Disparities

BACKGROUND: Recent studies have reported on the changing epidemiology of colon cancer. Given this cancer's high prevalence and mortality, defining high risk groups will be important to guide improvements in cancer screening programs. METHODS: A retrospective cohort study of a large population-based cancer registry in the United States from 1973-2004 was performed to analyze the race and sex-specific disparities in colon cancer epidemiology. RESULTS: Blacks and females demonstrated the greatest proportions of proximal cancers: the incidence rate of proximal cancers among black males was more than double that of Asian males (25.2 per 100,000/year vs 11.7 per 100,000/year, p < 0.0001) and the rate among black females was twice that of Asian females (21.9 per 100,000/year vs 11.4 per 100,000/year, p < 0.0001). Blacks as a group had the highest rates of advanced cancers: the rate among black males was nearly double that of Hispanic males (17.1 per 100,000/year vs 8.7 per 100,000/year, p < 0.0001) and the rate of advanced cancers among black females was twice that of Hispanic females (12.4 per 100,000/year vs 6.2 per 100,000/year, p < 0.0001). CONCLUSIONS: This study demonstrates marked disparities in the sex-specific and race/ethnicity-specific epidemiology of colon cancer. These differences likely represent unequal access to health care resources and race and sex-specific variations in cancer biology. An individualized approach incorporating these disparities would benefit future research and guidelines for improvements in cancer screening programs.