The American Cancer Society is adding three new colon cancer screening tests to its recommendations.
The move is designed to get more people tested more regularly as rates of young people diagnosed with colorectal cancer tick up.
“People should be getting screening as soon as they are eligible,” epidemiologist Robert Smith, senior vice president of early cancer detection science at the American Cancer Society, told Business Insider, shortly before the new recommendations were announced on Wednesday. “We always say the best test is the one you get.”
Everybody aged 45 to 75 should be getting regular colon cancer screenings, according to both ACS and federal guidelines. But recent survey data show that less than half of US adults aged 45 to 49 have completed their routine colon cancer screenings, even as young colorectal cancer cases are on the rise.
Colonoscopies remain the best option because a doctor can examine and remove any suspicious tissue in a single procedure. But people sometimes skip them because they require prep (cleaning out the colon with laxatives), sedation, and recovery time. Plus, doctors’ offices can be booked weeks or months in advance, making scheduling challenging.
Until today, the ACS has endorsed colonoscopy and some more rudimentary stool tests. Now, the organization has given its blessing to three new, higher-tech tests: a blood test and two more sensitive at-home stool tests. Not all of these options are equally effective, though.
Stool tests are a tried-and-true alternative to visual exams at a doctor’s office
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Collecting stool out of the toilet has been a simple, cost-effective colon cancer screening strategy for decades. Older tests only looked for blood in stool, which could help screen for cancer, but might also catch other conditions like hemorrhoids.
The two new stool tests being recommended today are called Cologuard Plus and ColoSense. They use some of the same techniques as previous stool tests, but are more accurate and sensitive to cancer and pre-cancerous polyps. That’s because they go beyond checking for blood in stool and look for tell-tale signs of cancer being shed into the bloodstream. Cologuard Plus looks for DNA shed from tumors, like regular Cologuard, but then also checks for cell-free DNA. ColoSense looks for cancer RNA in the stool.
“They’re much more sensitive than the standard high-sensitivity fecal immunochemical test,” Smith said, referring to the inexpensive FIT at-home colon cancer tests, which have been available over the counter for years.
FIT tests typically detect about 80% of colon cancers when performed annually, while Cologuard Plus and ColoSense both detect cancer more than 90% of the time, according to peer-reviewed studies, and only need to be performed every three years.
“If someone’s 45 years old and they don’t have a family history,” Smith said, “a high-sensitivity stool test would be a simple thing to do.”
A new blood test is arguably more convenient, but not quite as good at catching cancer
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The ACS is also recommending, for the first time, a blood test to screen for colon cancer. It is the Shield test from Guardant Health, which was FDA-approved in 2025.
Studies suggest it can detect about 83% of the colorectal cancers that would be found during a colonoscopy.
The test picks up cancerous DNA shed by tumors in the blood, which means that as cancer grows and develops, the test gets better at finding it.
Unlike stool tests and colonoscopies, the test isn’t great at screening for precancerous polyps, which is why Smith says he would only recommend this new blood test to people who aren’t willing or able to do a visual exam like a colonoscopy or an at-home stool test.
“We want people to get tested,” he said. “Given how many people have not been recently testing or may be averse to any of the tests that we recommend, we might save quite a few more lives from premature deaths due to colorectal cancer if more people got a blood test who hadn’t gotten the other tests.”
All of the new tests ACS is recommending for colon cancer are typically covered by most major insurance plans, but coverage isn’t universal. Shield and Cologuard Plus are already covered by Medicare, while ColoSense is still under review.
Colonoscopies are still a doctor’s favorite — for good reason
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Colonoscopies, where doctors insert a long, flexible scope into the colon to look for cancer and clean out any precancerous “polyps,” are still the very best way to prevent and investigate cancer.
Dr. Andrea Cercek, section head of colorectal cancers at Memorial Sloan Kettering Cancer Center in New York, said her biggest fear with these new recommendations is that people may skip more regular colonoscopies in favor of a “fancy” blood or stool test.
“Colonoscopy obviously is still the best test to get, because we can not only detect cancer, but hopefully we detect polyps before they have the chance of developing into cancer,” Cercek said.
She worries patients could develop a false sense of security from the new tests, which are pretty good at detecting cancer, but can’t prevent it as a colonoscopy could.
“There exists this possibility of having a polyp that then goes undetected and could potentially develop into a cancer by the time that you get your next screening test,” Cercek said.
Any stool or blood test that comes back positive will also require a colonoscopy as follow-up. It’s a bigger chore, but with a better return on the investment, Smith said.
“Colonoscopy asks a lot of an individual: It’s generally a day away from work, they need to have a chaperone, they have to do a prep the night before,” Smith said. “But it offers very high performance in detecting cancer and advanced precursor lesions. And if your test is normal, you don’t have to do another one for 10 years.”
