New Guidelines for Colon Cancer Screening
At his Chelmsford gastroenterology practice, Dr. Richard Tilson is seeing a frightening trend. In the past year, he has diagnosed more colon cancer than he has in his career, particularly among adults who may think they are too young to be at risk.

Colon cancer is already the third-leading cause of cancer death in the United States. More than 50,000 are estimated to die of colon cancer in 2022, but for most, it is largely preventable. The rise of routine colon screening for adults over 50 has brought cancer rates down significantly over the past 20 years, but rates among adults 45-50 have begun to rise.
For that reason, the U.S. Preventive Services Task Force (USPSTF) recently lowered the recommended age to begin routine colon screens from 50 to 45.
Dr. Tilson explains the benefits of colon screening, and the risks of waiting too long.
The word screening often gets misinterpreted. We are not screening for colon cancer, we are screening for colon polyps that are precancerous. A Colonoscopy is a prevention test, and there are not many prevention tests in medicine. The only other cancers that we can significantly prevent medically are cervical cancer by getting the HPV vaccine, and liver cancer by getting the Hepatitis B vaccine. That’s it.
You develop cancer in your colon from very small growths called polyps. Once those polyps develop, they can eventually turn into colon cancer. We’re not very good at deciphering which polyps will turn into cancer, so during a colonoscopy we remove all of them.
About 8 years ago, the American Council of Gastroenterologists said people of African American descent should begin colon screening at 45, because evidence showed the rate of colon cancers started earlier in that population. Then in the last few years, they found that rates of colon cancers in the white population paralleled that of the African American population and they shifted the recommendation for everyone.
Learn more about the U.S. Preventive Services Task Force (USPSTF) recommendation.
It used to be in three different ways. There was a procedure called a flexible sigmoidoscopy that went into the end of the bowel, but we’ve learned that if you only look in 1/3 of the bowel, you miss 2/3 of cancer. There is also the Cologuard-style test that looks for blood and abnormal DNA in your stool, and finds about 92 percent of existing colon cancers. But by far the most accurate screen is with a colonoscopy, which looks at the lining of the bowel for polyps and then removes them. This prevents at least 95% of colon cancers that can occur.
The stool test misses about 1 in 12 cancers and about 60 percent of polyps. And because Colonoscopy visualizes and prevents Colorectal (Colon) Cancer, if you don’t have a high-risk profile you don’t need to have another one for 10 years. If you get one at 45, you are all set for 10 years.
If you have a family history with either a lot of people who have had Colorectal (Colon) Cancer or family members who have had a lot of different cancers, you should talk to a doctor, who may recommend getting colonoscopies every few years. There are also those who deal with chronic inflammation like Crohn’s disease or ulcerative colitis. Because inflammation can lead to a higher rate of cancer, they also get colonoscopies at a higher interval. If a Colonoscopy discovers a lot of polyps, that may also lead to a higher prevalence of surveillance.
When you get a Colonoscopy, you limit your diet for a day or so and take a really strong laxative to clean out the colon, which allows us to take a tube, a light and a camera to look through the bowel. Because it would be uncomfortable if we didn’t give you anything, we give you medicine to make you feel relaxed and not feel the procedure at all. Many find the preparation to be more unpleasant than the colonoscopy itself.
Because we use sedation to get people relaxed, you do need to take a day out of your life and not drive or work on the day of the test. You feel like you can go back to work, but you don’t want to do any high level thinking.
I’ve diagnosed more cancer this year than I have than in any year that I’ve practiced. We went almost a year where people delayed getting a test. A year makes a difference. To put things in perspective, it takes about 7-10 years for a small polyp to turn into cancer. But once it’s cancerous, it takes far less than that to where it may not surgically operable and it spreads.
Because this recommendation is put out by the U.S. Preventive Services Task Force (USPSTF), insurance is required to pay for every aspect of your colon cancer screening. In January of 2022, the federal government announced that insurance must also cover, without cost sharing, a follow-up Colonoscopy to evaluate a positive, non-invasive stool test like Cologuard, effective May 31, 2022.
To schedule your colonoscopy screening, contact your primary care provider or find a gastroenterologist affiliated with Lowell General Hospital at www.lowellgeneral.org/findadoctor. To speak to a Lowell General Hospital Physician Referral representative, please call 1-800-544-2424.