People most at risk for colorectal cancers do not get colonoscopies. In fact, up to 70 percent of people in the high-risk category — those age 50 to 75 — don’t seek testing.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
That’s unfortunate for these people because colorectal cancers are more preventable than other cancers. All colorectal cancers begin with a precancerous polyp, which can be removed, says James Church, MD, Head of the Section of Endoscopy at Cleveland Clinic.
“I can’t emphasize how preventable colon cancer is,” Dr. Church says. “You can’t prevent breast cancer, lung cancer or brain cancer in the same way. You can’t take precancerous polyps off any of those organs. It seems to me that colonoscopy must be done – that it can really save people’s lives.”
Colorectal cancer could be prevented in about 40 percent of patients through regular colonoscopies, says a study recently published in the New England Journal of Medicine.
Researchers followed nearly 89,000 participants for 22 years. During that time, 1,815 people developed colorectal cancer.
“The research demonstrates the importance of colonoscopy screening specifically,” Dr. Church says. “All other sorts of colon cancer screening are not the same.”
Dr. Church says it’s important to find an experienced colonoscopist who can spot polyps of different shapes and in locations that can be more difficult to find.
“You want to get the best colonoscopist you can. Somebody who knows how to recognize polyps and take them off in the safest way possible,” he says.
Besides being largely preventable, colorectal cancer also develops slowly, allowing time to discover and remove polyps.
“Every colon and rectal cancer arises from a polyp or other pre-cancerous lesion, and it takes 10 years on average for a polyp to become cancerous – which is why standard guidelines suggest colonoscopies once a decade starting at age 50.”
While this can be considered good news, there is an irony in it.
“Sadly, every patient who walks into my office with cancer had a polyp that could have been taken off,” Dr. Church says.
“They missed the boat for some reason: They were too scared, their family doctor didn’t recommend it, their insurance company wouldn’t pay for it, or they had a colonoscopy and their doctor didn’t see it.”
Most colorectal cancers occur in people age 50 to 75. However, he says a 42-year-old with bleeding from the bowel should not blithely assume that it’s just hemorrhoids.
If you have a family history of colorectal cancer, talk to your doctor for advice. Dr. Church says those with a family history may need a colonoscopy every five years, starting 10 years younger than the youngest relative who was diagnosed.
Take our colon cancer risk assessment! Also, find out more about colon cancer, including prevention.