Single Screening Cuts Colon Cancer Risk
Flexible Sigmoidoscopy Prevents Cancer, Reduces Need for Colonoscopy
"You'd think by now we'd see some sign of waning protection, but we see no waning at all," Atkin said. "I hypothesize it will last forever because I believe most of the polyps that are going to cause [left bowel] cancer are already there in your 50s. So all we have to do is look for them, find them, and remove them. And so far this hypothesis seems to be playing out."
Atkins and colleagues argue that in the government-funded U.K. health system, a single sigmoidoscopy at age 60 plus regular fecal occult blood test (a simple test for blood in the stool) will cut the colon cancer rate while lowering overall health care costs.
Implications for U.S. Colon Cancer Screening
What about the U.S., where the gold standard is colonoscopy every 10 years beginning at age 50?
Insight comes from John Monson, MD, chief of colorectal surgery at the University of Rochester, N.Y. Monson helped design the U.K. national training program that teaches nurses to perform sigmoidoscopies, and he also assisted in the design of the Atkin study (although he was not involved in the study itself).
"If you are fortunate enough to have insurance, assuming you are age 50 or so, then a colonoscopy is the right thing. But the reality is that large numbers of American patients do not have access to colonoscopy," Monson tells WebMD.
We shouldn't think of sigmoidoscopy as replacing colonoscopy, Monson says. Instead, we should think of it as a way to look for patients who truly need a colonoscopy.
"Flexible sigmoidoscopy is actually a very good use of health care resources to screen for people who should have a colonoscopy, which does have its downsides due to complications and costs," he says. "It is not simply flexible sigmoidoscopy, period. It is sigmoidoscopy followed by colonoscopy if you have certain findings. And it is pretty effective at preventing colon cancer."
The Atkin study appears in the April 28 online edition of The Lancet.