The American Institute for Cancer Research presented a comprehensive report on cancer prevention policy for a Congressional briefing on Capitol Hill last month. The report concluded over 45 percent of colon cancer cases and 38 percent of breast cancer cases in the U.S. could be prevented by making changes in our diet, physical activity and weight control. In 2006, a total of 15,918 new cancer cases were diagnosed in Iowa. Of that number, 1,858 were colon cancer and 2,156 were breast cancer.