INDIANAPOLIS, June 5 (UPI) -- Colon cancer screenings offer limited benefits to patients under age 50, a study released Wednesday suggests, so current recommendations for regular colorectal testing after 50 should remain unchanged.
Researchers led by Dr. Thomas F. Imperiale, professor of medicine at the Indiana University School of Medicine and a research scientist at the Regenstrief Institute for Healthcare, studied data on colonoscopies of 906 individuals ages 40 to 49. The patients had no known genetic risk for colon cancer or exhibited any symptoms, such as rectal bleeding or abdominal pain.
No cancer was found in any of the patients, the researchers report in the June 6 issue of The New England Journal of Medicine.
People under age 50 are not risk-free for colorectal cancers, however. About 7 percent of such cancers do strike this age group, Imperiale said. For now, he advised routine colon cancer screenings for those age 50 and older, although he acknowledged age might not be the best factor in deciding who should undergo screening.
"Our findings do create tension with the fact that cases of colon cancer in people of average risk do occur before age 50," Imperiale told United Press International. "Ideally, if screening could be more risk-based than it is, that would serve people better."
In the meantime, he added, "this study provides some reassurance that we're at least in the right ballpark. I think the recommendations right now serve the public health quite well."
Screening forty-somethings could actually increase complications among a small percentage of people, such as perforations during the colonoscopy. For those in their 40s who have a family history of colon cancer or other types of cancer and who also have a history of colorectal polyps, colonoscopy screening would be recommended, Imperiale said.
To examine more closely why some younger people develop this disease, Imperiale and his colleagues have launched a pilot study to look for risk factors for precancerous and cancerous colon polyps in individuals who are younger than 50 and who have no known genetic risk factors.
The National Cancer Institute reports colorectal cancer is the second leading cancer killer in the United States. An estimated 90 million people -- about one-third of the population -- are at risk for developing the disease. In 2002, nearly 150,000 people will be diagnosed with the cancer and about 56,600 will die from it, NCI reports. Only lung cancer kills more Americans.
Everyone at least 50 years old is considered at some risk. Other factors include a diet low in fruits and vegetables and high in animal fat, a family or personal history of colorectal polyps or cancer, obesity, alcohol consumption, tobacco use, and a condition known as inflammatory bowel disease. NCI advises regular screenings after age 50 to find polyps that can be removed before they turn into cancer. When colorectal cancer is detected early, the institute reports, chances of being cured are very good.
(Reported by Katrina Woznicki, UPI Science News, in Washington)
