Well-Rounded Prevention May Lower Colon Cancer Risk
Feb. 4, 2002 -- You've often heard prevention is the best medicine, and you may even know some of the items you need to help prevent colon cancer are right in your medicine cabinet. But did you know that any colon prevention plan is not complete without lifestyle changes and routine screening exams that you probably aren't getting?
Research suggests that aspirin, nonsteroidal anti-inflammatory drugs, the vitamin folate, and the mineral calcium, all may have a protective effect against colon cancer. Estrogen, too, may have a protective effect.
Although these medicines and supplements may help reduce colon polyps and help prevent their progression to cancer, they probably aren't enough by themselves, according to a report in the June 29, 2000, issue of The New England Journal of Medicine.
Colon cancer is the second most prevalent cancer in the U.S. One-third of all adults develop polyps, which often turn into cancer, by the age of 50, and half by the age of 70.
"The best way to lower your risk of colon cancer is to reduce red meat intake, exercise regularly, stop smoking, and control your weight," says study author Pasi Janne, MD, PhD. "Annual stool testing and other screening methods are also critically important." At the time of the study, Janne was an oncology fellow at Boston's Dana-Farber Cancer Institute.
In a survey of more than 600,000 adults, aspirin reduced the risk of colon cancer death by 40%, when taken 16 times per month or more. Similarly, the nonsteroidal anti-inflammatory drug Clinoril (sulindac) significantly reduced polyps in high-risk people. Both aspirin and Clinoril can cause stomach bleeding, but the new nonsteroidal anti-inflammatory drug Celebrex may prevent colon polyps without this side effect.
The nutrients folate, also known as folic acid, and calcium also can lower the risk of colon cancer. Most studies show that as dietary or supplemental intake increases, the risk of both polyps and colon cancer decreases. Surprisingly, several large studies did not show a benefit of fiber or vitamins A, C, D, and E for colon cancer prevention.
During the last 20 years, postmenopausal hormone replacement therapy has been credited for the decline in colon cancer among women. In fact, two studies showed a risk reduction of up to 20%, but the benefit may be greatest in women currently receiving estrogen therapy.
Doctors say aspirin protects against heart disease as well. "To lower the risk of heart attack, cardiologists have been prescribing coated aspirin for years," says Karen Antman, MD, director of the Herbert Irving Comprehensive Cancer Center and professor of medicine at Columbia University in New York City. "And all the better if it reduces the risk of colon cancer."
But early detection is the best way to prevent colon cancer death. A narrow tube, equipped with a camera, allows doctors to see inside the bowel and remove polyps as needed. "Less than a third of adults over age 50 are getting endoscopic exams every five years as recommended," Antman cautions, "and most of them are getting only half of their colon screened."