Replacing a Colonoscopy With At-Home Tests Sounds Good, But Doesn’t Necessarily Work

At-home screening tests are becoming more and more prevalent across all cancers, including colorectal cancer. But can sending out a stool sample really be as effective as going into your doctor’s office and having a colonoscopy? The short answer is no.

Colon cancer is one of the most common cancers in the United States … it’s expected to kill more than 50,000 Americans this year. It’s also an extremely preventable cancer. That’s why screening is so important, and not just for people who are considered high-risk. Even though the at-home colon cancer test Cologuard is 93% effective – that’s still 7% of people who will have their cancers missed. A colonoscopy is still the best tool for detecting cancer.

“Many of the stool tests are good screening tools, meaning that they look for blood or pre-cancerous or cancer cells,” says Dr. Heather Yeo, a colorectal surgeon at NewYork-Presbyterian/Weill Cornell Medical Center. “But they must be done more frequently. They can miss polyps and some cancer … and if [the results] are concerning a colonoscopy should be done.”

Still, a lot of people are taking advantage of the convenience of the at-home Cologuard test. More than 1.3 million people have used the test, according to an article written by Dr. Naresh Gunaratnam for Stat News. “Cologuard tests stool for tiny amounts of blood as well as for certain abnormal sections of DNA in cells shed by cancer or polyps that end up in the stool,” Dr. Gunaratnam writes. It is a good screening test, that’s not being called into question in Dr. Gunaratnam’s article or this one … but it’s not as good as a colonoscopy.

Colon cancers begin as polyps 95% of the time. A study published in 2014 in the New England Journal of Medicine found that the Cologuard test misses more than 30% of polyps that will soon become cancer, and 57% of polyps that may become cancer. That’s a big discrepancy. Especially since when polyps are found during a colonoscopy, doctors can essentially stop cancer from growing before it even starts.

The real question here becomes, is it worth it to use a less effective test to avoid the inconvenience and awkward experience of having a colonoscopy? Because it is such a preventable disease, and a disease that has a really high survival rate if caught early, Dr. Zuri Murrell, a colorectal surgeon at Cedars-Sinai Medical Center, says it’s worth it to just deal with the inconvenience of the colonoscopy.

“You shouldn’t die from fear and you shouldn’t die from embarrassment,” Dr. Murrell says. “Those are really the only two reasons people are dying from this disease today. If I tell you that colorectal cancer is the third most common cancer … how can I also say that it can almost be completely prevented?”

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