Colorectal cancer--Prevention and detection.

The American Cancer Society estimates that during 1980, there will be approximately 114,000 new cases of colorectal cancer in the United States--second only to lung cancer (an expected 117,000 cases) in incidence for internal malignant neoplasms. There will be 53,000 deaths this year from colorectal cancer. The low five-year survival rate of 42% in related primarily to late diagnosis. Therefore effective methods of making an earlier diagnosis are important. The use of fecal occult blood testing and sigmoidoscopic examination (rigid or flexible) appear to be tools that will make earlier diagnoses of colorectal cancer. Colonoscopy and barium enema are indicated if symptoms of colorectal cancer are present or if indicated from findings noted on fecal occult blood testing or sigmoidscopy. Determinations of carcinoembryonic antigen levels are of no practical value in colorectal cancer screening. In asymptomatic patients, fecal occult blood testing is recommended annually beginning at age 50, while sigmoidoscopy should be performed at age 50, repeat in one year, then performed every three years. The two chief areas of interest in colorectal cancer prevention are the removal of neoplastic polyps at the time of endoscopy, and the role of nutrition to decrease fat and increase fiber in the diet.