Colonoscopy Study Causing Concerns

Colonoscopies have been considered the gold standard for colorectal cancer screening and prevention for decades. Now, however, a new study seems to call that belief into question, but health professionals argue the research can be easily misinterpreted.

The study, published in the New England Journal of Medicine, followed 85,000 participants over a ten-year period. Trial participants were either invited to undergo a single colonoscopy screening or to receive their usual physician care with no colonoscopy.

Of those who were invited to have colonoscopies – whether they got one or not – there was an 18% reduction in developing the disease, and no significant reduction in the likelihood of colon cancer death.

Dr. Omar Khokhar is an OSF HealthCare gastroenterologist in Bloomington, Illinois. He says there is a sticking point in this study, which can be easily overlooked: Less than half (42%) of the group invited to get a colonoscopy actually went through with the screening. If you concentrate on those individuals only, the benefits of screenings are more apparent.

“The 42% of people who accepted the invitation for the colonoscopy arm of this study had a 31% reduction in colon cancer incidents, and a 50% mortality reduction from colon cancer,” Dr. Khokhar explains. “So I think if anything, this study tells us that if you get screened, if you get a colonoscopy, you will have a reduction in your risk of colon cancer, and death from colon cancer.”

The new study has gotten quite a bit of media attention, and the major concern from physicians is that prospective patients will see the headlines and then possibly not pursue screenings if they believe there is no significant benefit.

Dr. Khokhar says he and his colleagues welcome patients’ questions, especially from those who have concerns. He says part of his job is to explain the ins and outs of screenings, and allow patients to decide what type of care they prefer.

“There are things that we're experts on and we're not experts on, and I'm fully open to an informed patient. I encourage that conversation. Come to me armed with your data. I'll come with my data. And let's talk about it and then you can decide which risks you want to live with,” he says.

“It's simple to say I don't want to get it done. Then you're choosing the risk of not getting it done, and with 52,000 colon cancer deaths every year in this country, and the chance of getting colon cancer one in 25, which is 4% - it's not insignificant - then you choose to live with that risk. But ultimately, as a patient, you get to decide to at least have the conversation.”

The American Cancer Society recommends that all people at average risk of colorectal cancer start regular screening at age 45. However not all colorectal cancer screenings are created equally, and according to Dr. Khokhar, there is a reason the colonoscopy is considered the gold standard. Colonoscopies allow physicians to view the entire colon and both detect and remove polyps, small clumps of cells that can develop into cancer, during the same procedure.

“This is the only test where we can find a precancerous lesion and remove it at the same time,” says Dr. Khokhar. “The stool based tests, if they're negative, you have a clean bill for one to three years depending on which one you choose. If they are positive that needs to be followed up with a colonoscopy to make sure you don't have a precancerous polyp that we can address and get rid of during this colonoscopy.”

Lower risk patients may be eligible for one of several other non-invasive tests, including at-home stool tests Dr. Khokhar mentioned. These tests, including Cologuard, can be done outside of a physician’s office and can detect blood in the stool or abnormal DNA that may suggest cancer.

Colorectal polyps and colorectal cancer don’t always cause symptoms, especially at first. That is why getting screened regularly for colorectal cancer is so important. If you do experience symptoms, they may include a change in bowel habits, blood in or on your stool (bowel movement), abdominal pain, aches, or cramps that don’t go away or unexplained weight loss. If you have any of these symptoms, talk to your doctor.