What Colon Cancer Test Is Best for Women?
Colonoscopy Identifies More Cancers in Women, Researchers Say
May 18, 2005 -- Colonoscopy may be the "preferred
method of screening" for colon cancer and rectal cancer in women, say
doctors in The New England Journal of Medicine.
No colon cancer screening test is perfect. It's possible for colonoscopy (or
any screening method) to miss some cancers or polyps. However, colonoscopy may
be a woman's best test, shows the study by researchers including Philip
Schoenfeld, MD, of the University of Michigan's medical school.
Colon cancer is the third most common cancer found in men and women in the
U.S. (not counting skin cancer), says the American Cancer Society (ACS). The
ACS expects nearly 105,000 new cases of colon cancer, more than 40,000 new
rectal cancer cases, and more than 56,000 deaths from both kinds of cancer this
Early Detection Saves Lives
The death rate for colorectal cancer has been dropping for 15 years, says
the ACS. Early detection can greatly improve chances of survival.
The ACS recommends that men and women of average risk begin screening at age
50. Those with certain risk factors should begin screening earlier, says the
Screening methods include colonoscopy, "virtual" colonoscopy,
flexible sigmoidoscopy, fecal occult blood tests, and double-contrast barium
enemas. Other studies have shown colonoscopy detects more cancers.
A colonoscope is a longer version of a sigmoidoscope. It's a thin, lighted
tube with a tiny camera that doctors use to look inside the colon. A
colonoscope can be guided all the way along the colon. A sigmoidoscope only
lets a doctor see about half of the colon, says the ACS.
Latest Colon Cancer Test Findings
Schoenfeld and colleagues studied more than 1,400 women aged 50-79. The
women had an "average risk" of colorectal cancer, says the study. A
total of 230 women (about 16%) had a family history of colon cancer.
The women filled out detailed questionnaires about risk factors before
While everyone is at risk for colon cancer, traditional risk factors for
colon cancer include:
- Age. Risk increases with age.
- Sex. Women are at a higher risk for colon cancer while men
have a higher risk for cancer of the rectum.
- Family history. Parents, siblings, and children of a
person who has had colorectal cancer are somewhat more likely to develop
colorectal cancer themselves.
- Diet. Diets high in fat and calories and low in fiber are
linked to this cancer.
- Polyps. These noncancerous growths are common in people
over the age of 50. A certain type of polyp, called adenomas, is considered
The researchers estimated the number of cancers, polyps, and other problems
that would have gone undetected if the women had only gotten sigmoidoscopy.
Colonoscopy identified cancers and polyps in 72 women (5%). Only 35% of
those women would have had those lesions identified if they had only gotten
sigmoidoscopy, says the study.