Earlier Colon Cancer Screening?
Study Shows People Get as Many Colon Polyps in Their 40s as in Their 50s
May 15, 2008 -- On your 50th birthday, you'll get a present from your doctor
-- a referral to
colon cancer screening, preferably by colonoscopy.
But a new study suggests this gift might do more good if it arrives years
Most people don't get colon cancer before they're 60. Although
colon cancer is deadly, it takes about a decade for
colon polyps to turn into cancer (if they do -- most polyps never
become cancers). Removal of polyps prevents colon cancer, so doctors start
looking for polyps when a person turns 50.
Should doctors start looking earlier? A new study shows that people in their
40s are just as likely to have colon polyps as are people in their 50s. Study
leader Alfred I. Neugut, MD, PhD, is acting chief of oncology at Columbia
University Medical Center.
"Should we start screening people in their 40s? Maybe," Neugut tells
WebMD. "It does take 10 years for a polyp to turn into cancer. So if people
had screening in their 40s, maybe you would not see cancers in people in their
Neugut is quick to point out that this small study is by no means
definitive. For one thing, there were too few patients. And the study did not
evaluate whether the patients had family histories of colon cancer -- a risk
factor for colon cancer that should trigger screening before age 50.
(Have you been screened
for colon cancer? How old were you when you had your colonoscopy? Talk with
WebMD's Active Aging message board.)
The study looked at colonoscopy results from 553 people aged 40 to 49 and
from 352 people aged 50 to 59. All of these people received colonoscopies as
part of a corporate health-screening plan.
- 14% of 40-somethings and 16% of 50-somethings had one or more polyps.
- 2% of 40-somethings and 3.7% of 50-somethings had a polyp that was becoming
- None of the 40-somethings and one of the 50-somethings had colon
"I see colon cancer patients, and I see a lot of 52- and
53-year-olds," Neugut says. "If we had caught their polyp when they
were 47, I would not be talking to them when they were 52. I can't say that
this study should lead to a change in screening policy, but we should consider
it. Maybe we could compromise and say people should start screening at age
Robert A. Smith, PhD, director of cancer screening for the American Cancer
Society, doesn't think this is a good idea. He points out that since Neugut and
colleagues did not know why their 40-something subjects agreed to
colonoscopies, a significant number of them might have family histories of
Moreover, Smith says, if most of the people with polyps were in their late
40s, screening at age 50 would catch them before the polyps became cancers.
"And there is a rate of harm to colonoscopy," Smith tells WebMD.
"If you start doing colonoscopies at younger ages, with less risk of colon
cancer, you may be looking at a net harm instead of a net benefit."
Neugut says he isn't going to start advising colonoscopies for healthy
40-somethings without a family history of colon cancer.
"But if a healthy 45-year-old walked in the door and said, 'I want a
colonoscopy,' I would not deter him," he says. "In the past, I might
have tried to talk him out of it. So this study changes my practice to that
Neugut and colleagues report their findings in the May issue of