A simple, cheaper exam of just the lower part of the bowel can cut the risk of developing colon cancer or dying of the disease, a large federal study finds.
Many doctors recommend a more complete test — colonoscopy — but many people refuse that costly, unpleasant exam. The new study shows that the simpler test, flexible sigmoidoscopy, can be a good option. Although it may seem similar to having a mammogram on just one breast, experts say that even a partial bowel exam is better than none.
The study was published online Monday by the New England Journal of Medicine.
Colorectal cancer is the second leading cause of cancer deaths in the United States and the fourth worldwide. More than 143,000 new cases and 52,000 deaths from the disease are expected this year in the United States alone.
People ages 50 to 75 who are at average risk of colon cancer are urged to get screened, but only about 60 percent do. Government advisers recommend one of three methods: annual stool blood tests; a sigmoidoscopy every five years plus stool tests every three years; or a colonoscopy once a decade.
Sigmoidoscopy is not a popular choice in the United States but it's the one used most often in England. It can be done in an ordinary doctor's office and costs just $150 to $300 versus $1,000 to $2,000 for a colonoscopy.
One drawback: A sigmoidoscopy is done without anesthesia. The test usually isn't painful, but patients feel cramping and some discomfort, said Dr. Durado Brooks, the American Cancer Society's colon cancer expert. It also sees only the lower one-third of the colon, "but that is an area where probably half of polyps and cancers develop," Brooks said.
The new study, led by Dr. Robert Schoen of the University of Pittsburgh Medical Center, tested how well it works. The research was sponsored by the federal National Cancer Institute.