Each year, 150,000 Americans will be diagnosed with colorectal cancer. The best chance of a cure is with early detection.
Charles Yeh, 74, likes taking care of his fish. A few years ago he was the one in need of care after doctors found a suspicious polyp during a sigmoidoscopy.
Charles Yeh/ Sigmoidoscopy Patient: "They decided that it is suspicious, an odd shape normally can become cancerous, so they said I should have it out."
Sigmoidoscopy examines only the lower half of the colon, as compared to a colonoscopy which examines the entire colon.
Robert Schoen, M.D./ University of Pittsburgh: "The data shows very clearly that colorectal cancer screening does prevent death, and it probably can even prevent you from developing the disease to begin with."
Most physicians recommend people age 50 and older have sigmoidoscopy every five years, or colonoscopy every ten. But a new study in the Journal of the American Medical Association says that may not be often enough.
Researchers studied more than 9,000 people who had had a negative sigmoidoscopy. They had them come back three years later for another sigmoidoscopy, instead of waiting the customary five years. Here's what they found.
Among those 9,000 people, 1,300 had an abnormal exam. About 300 of those had pre-cancerous lesions, including 78 with advanced lesions or actual cancer.
Robert Schoen, M.D./ University of Pittsburgh: "We found 0.8 percent of subjects, about one percent, who had these either cancer of these advanced pre-cancer lesions."
Charles Yeh is glad he didn't wait too long to have another exam. His polyps could have turned into cancer if he hadn't caught them with the second sigmoidoscopy.
"It's not very uncomfortable. It's easy. It does not take too much time, and also it has a lot of benefits," he says.
Eighty percent of the serious lesions were in a part of the colon that appears to have been well examined the first time around.
That suggests these lesions can crop up in a shorter period of time, and could mean we need to do more frequent screening with both sigmoidoscopy and colonoscopy.