An estimated 130,200 cases in 2000, including 93,800 of colon cancer and 36,400 of rectal cancer.
Colorectal cancers are the third most common cancers in men and women.
Research suggests that these declines may be due to increased screening and polyp removal, preventing progression of polyps to invasive cancers. Mortality rates for colorectal cancer have also declined for men and women over the past 20 years. This decrease probably reflects the decreasing trends in incidence rates and the increasing survival rates. Recent studies have suggested that estrogen replacement therapy and nonsteroidal antiinflammatory drugs such as aspirin may reduce colorectal cancer risk. A digital rectal examination should be done at the same time as sigmoidoscopy, colonoscopy, or double-contrast barium enema.