Colonoscopy Crowned Best for Detecting Colon Cancer
Douglas Rex, MD, is one of the authors of the American College of Gastroenterology's current screening guidelines. Those guidelines recommend a first colonoscopy at age 50 for those with average risk and a follow-up colonoscopy every 10 years thereafter. Rex tells WebMD that "Imperiale tends to be very cautious. There is a significant jump in colon cancer beginning at age 50 and continuing through age 60, and then it levels off with age." Rex is a professor of medicine at Indiana University and is a partner in the same practice as Imperiale.
David A. Johnson, MD, also a co-author of the guidelines, says he too thinks both studies make the case for colonoscopy.
Johnson, a professor of medicine at Eastern Virginia Medical School in Norfolk, says, "Colonoscopy is the best evolving screening modality that we have, and it should be utilized without waiting for symptoms." He says that for some reason -- possibly a change in diet or other environmental factor -- colon cancers have moved from their historic location low in the rectum to higher in the colon.
He adds that screening tools have also evolved from the rigid sigmoidoscope, which was adequate in the 1930s, to the use of flexible sigmoidoscopy. "But with this tremendous shift in position, even with the flex sig you can't get in there. That's why in the last several years, there has been a recognition of the need for whole colon imaging."
Johnson says the American College of Gastroenterology is so pro-colonoscopy that it has decided to launch an effort in "10 to 15 key states, including New York, to introduce model legislation that will require health insurance companies to cover screening colonoscopy." He says that Virginia already has such a bill, which was introduced by state Sen. Emily Couric, sister of TV personality Katie Couric, whose husband died as a result of colon cancer. He says the state campaigns will begin in full force this fall.
- Colorectal cancer doesn't usually cause any symptoms in the early stages of the disease, when it is most treatable, so it is important to be screened to discover any growths that could lead to cancer.
- New research shows that colonoscopy is a superior screening method to flexible sigmoidoscopy, because it examines the whole length of the colon, not just the lower half.
- The use of colonoscopy is still somewhat controversial, because it is more expensive and requires anesthesia.