Harvard Health Content API

Screening tests for colon cancer reduce deaths by one-third to one-half, 2 new studies find. The first study included nearly 89,000 health professionals. Researchers kept track of them for about 22 years. People who had a screening colonoscopy that found no problems were 56% less likely to die of colon cancer than those who had no screening tests. Colon cancer deaths were 40% lower for people who had a screening sigmoidoscopy that found no problems. Both tests look at the inside of the colon. A colonoscopy looks at the whole colon. A sigmoidoscopy looks at only the lower portion. A second study randomly divided 46,500 older adults into 3 groups. Two groups received fecal occult blood tests. This test looks for blood in the stool, which can indicate possible colon cancer. The third group received “usual care.” Few people in this group got the test.