Finding cancer with an at-home test

Author: Leslie Toldo

If you have been a little on edge about getting a colon cancer screening, recent TV commercials featuring people literally singing about the ease of the Cologuard at-home test might just put your mind at ease.

It sounds simple enough. You get a doctor’s prescription; the test kit comes in the mail; you follow the simple instructions, ship your sample to a lab, and wait for the results.

It may sound too good to be true, but Karmanos Cancer Institute at McLaren Flint surgical oncologist Dr. Scott Kizy says these tests are a good option for some people.

“These tests detect different markers in your stool to look for cancer and polyps,” Dr. Kizy said. “The older tests just looked for blood in your stool, and they weren’t very accurate when used alone. The newer Cologuard test looks for blood and DNA in your stool and has a higher accuracy finding polyps and cancers.”

However, taking the at-home test is no guarantee you won’t need a colonoscopy. You will need a follow-up colonoscopy if the Cologuard test shows evidence of cancer or a polyp. That is because the colonoscopy, considered the gold standard for colorectal cancer screening, does much more than give a snapshot of any irregularities in your colon or rectum.

“A colonoscopy allows a specialist to look at the entire surface of the colon and rectum,” Dr. Kizy said. “They look for polyps, which are small mounds protruding from the colon wall. They can remove these polyps and biopsy any other concerning findings.”

The day before the procedure, patients do a bowel prep at home. Then, under light anesthesia, a doctor places a colonoscope into the rectum to get a look at the colon. The procedure requires at least one day off work, and you may also want to take off for the day before prep.

“In talking to patients, the bowel prep is the most unpleasant part of a colonoscopy, but it is doable,” Kizy said.  

If you are at high risk for colorectal cancer, the American Cancer Society recommends a colonoscopy. Your doctor may even advise getting one every 3 to 5 years, starting at age 45 or earlier. Those considered high risk have histories of colon polyps or cancers, close relatives who have had colon cancer, or suffer inflammatory bowel disease or certain cancer syndromes.    

The at-home stool sample tests, like Cologuard, may be an excellent option for everyone else- people considered average risk. Starting when you are 45, you can take the screenings, usually every three years, so long as the tests come back negative. The other option is having a colonoscopy which, if it comes back negative, you will only need to repeat every ten years.

No matter what test you choose, Dr. Kizy says, the important thing is that you keep up with routine screening. “As a surgical oncologist, I’ve seen the power of screening in the early detection and prevention of cancer, especially colorectal cancer.”

Talk to your primary care physician to learn more about the screening options available and find the one that is best for you. Learn more about colon cancer and your screening options at