At-home stool tests for colorectal cancer screening are rising in popularity, but are they right for you?

March marks the beginning of Colorectal Cancer Awareness Month.

March 5, 2023, 10:06 AM

At-home stool tests can be an easier way to screen for colorectal cancer than a dreaded colonoscopy. As the rates of the cancer continue to rise in younger people, home tests might help improve detection and get people treated sooner.

March marks the beginning of Colorectal Cancer Awareness Month. Colorectal cancer is the third most commonly diagnosed and third most common cause of cancer deaths in the U.S., according to the American Cancer Society. Diagnosis of the disease is on the rise among younger people under age 55, according to a new study from the ACS, and it’s being diagnosed at more advanced stages.

That’s why the American Cancer Society is reminding people that any screening for colorectal cancer can save lives. Adults with average risk should get screened starting at age 45, according to the U.S. Preventive Services Task Force.

“Identifying cancers earlier make it a lot easier to treat”, Dr. Jeffrey Farma, a surgical oncologist and interim chairman of surgery at Fox Chase Cancer Center, told ABC News.

At-home stool tests, where people collect stool samples and send them to a lab, can help make the process easier for some people. Here’s how to know if this is a good option for you.

Who is a good candidate for at-home stool tests?

The first step is to have a discussion with your doctor about whether you qualify for at-home stool tests given your family history and medical history.

Only people with “average” colorectal cancer risk – who don’t have any family or medical history that makes them high-risk — can use the tests. High-risk individuals aren’t eligible, experts say.

High-risk individuals are those with colon cancer in a first-degree relative (like parents or siblings), or personal or family history of a higher risk polyp in the colon or rectum. Those people should “only get screened with a colonoscopy”, Dr. Fola May, a gastroenterologist, quality director and health equity researcher at UCLA Health, told ABC News.

PHOTO: A doctor talks to a patient in this undated stock photo.
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Other high-risk individuals for colorectal cancer are those with inflammatory bowel disease such as Crohn’s disease or ulcerative colitis, and people with genetic conditions that put them at risk for cancers.

People at increased risk may need to start screening for colorectal cancer earlier and get tested more often.

What are the available at-home stool tests?

Several at-home stool-based tests exist.

These tests check the stool for signs of cancer such as blood, unusual changes in DNA, or both. There are a few types of tests. Some, like the fecal immunochemical test, are done every year. Others, like stool DNA tests, only need to be done every three years.

Companies offering these tests include Cologuard, Labcorp, or QuestDirect. Talk to your doctor about which one is best for you.

What are the pros and cons of at-home tests?

The biggest advantage to at-home stool tests is that they can be done in the comfort of your own home.

That convenience is one reason why the rate of colorectal cancer screening was stable in the second year of the pandemic, a recent study found, even when rates of other types of cancer screening went down. “The pandemic pushed everyone to think about more convenient or more person-centric ways to get cancer screening completed”, Dr. Arif Kamal, Chief Patient Officer for the ACS, told ABC News.

Additionally, unlike a colonoscopy, at-home stool tests do not require patients to take the unpleasant step of clearing out their bowel with fluids, pills, enemas, or a combination. Patients also will not need sedation or need to miss a day of work to do the stool test.

While not leaving your house adds a large appeal to at-home stool tests, they’re not always as accurate as a colonoscopy. They can miss many polyps and some cancers. Some stool-based tests may also be affected by your diet or drugs you take.

Is a colonoscopy still needed?

Doctors stress that while these at-home stool tests may be more convenient and done in the comfort of home, if any of these test are abnormal, you’ll still need a colonoscopy.

“If you don't get that second step, colonoscopy, you have not completed the screening process and are more likely to get and die from colorectal cancer,” May says.

You should also talk to your doctor about timely colorectal cancer screening if you have changes in bowel habits, blood in your stool, diarrhea, constipation, feeling your bowel does not empty all the way, abdominal pain, aches, cramps that do not go away, or unexplained weight loss, according to the Centers for Disease Control and Prevention.

Get screened, in any way

The ACS estimates that in 2023, approximately 153,020 people will be diagnosed with colorectal cancer in the U.S., and 52,550 people will die from the disease, including 19,550 cases and 3,750 deaths in individuals younger than 50.

Colonoscopies are the gold standard for colorectal cancer screening, but experts say any test is better than no test — which is where at-home stool testing comes in.

“The best cancer screening is the one that gets done,” Kamal said.

Kimberly Loo, MD is an internal medicine resident at New York-Presbyterian/Weill Cornell Medical Center, and a contributor to the ABC News Medical Unit.