More Ways To Get Screened For Colon Cancer: New Tests Aim To Break Down Colonoscopy Anxiety, But Experts Say There’s Still One True ‘Gold Standard’

“In short, more options mean more people might get screened. This is a good thing,” says Dr. Kyle Cologne, a board‑certified general and colorectal surgeon at Keck Medicine of USC.

“Some people may not want to do one screening test, so the more choices we can offer, the more likely they are to get screened,” Dr. Cologne adds.

A colonoscopy uses a long, flexible tube with a camera to examine the colon and rectum. If no polyps are found, most people won’t need another screening for ten years.

Polyps themselves aren’t cancer, but they can become cancerous over time, which is why removing them early is so important.

The updated ACS recommendations reaffirm that average‑risk adults should begin screening at age 45 and continue through age 75 if they have a life expectancy of at least 10 years.

What’s new is the addition of a blood‑based screening option performed in a doctor’s office, along with one updated and one brand‑new at‑home stool‑based test that look for hidden blood and molecular markers.

“Blood‑based and stool‑based tests may increase participation among patients reluctant to undergo colonoscopy,” says Dr. Alessio Pigazzi, Director of the Division of Colorectal Surgery at Cedars‑Sinai.

But he cautions that “these screening methods are not equivalent in preventive capability.”

Dr. David Robbins,  a board-certified gastroenterologist and vice chief of gastroenterology at Northwell’s Lenox Hill Hospital, underscores the same note of caution.

“At‑home stool tests and newer blood‑based screening options are available, but they come with a major trade‑off,” he tells SurvivorNet.

“They detect only about 13% of advanced precancerous lesions — meaning they miss most of the lesions whose removal actually prevents cancer. And any positive result on a non‑colonoscopy test, whether stool or blood, still requires a follow‑up colonoscopy,” Dr. Robbins added.

Dr. Cologne also notes that national screening rates have hovered around 60–80 percent, and with expanded screening options, experts hope more people will receive screening.

What’s New in the Guidelines

Updated and new multi‑target stool tests:

• Next‑generation mt‑sDNA test (Cologuard): An improved version of the existing at‑home DNA‑based stool test that detects specific DNA markers and hemoglobin.
• mt‑sRNA test (ColoSense): A new at‑home test that analyzes stool for RNA markers and hemoglobin.

Blood‑based screening:

• Blood‑based test (Shield): Detects tumor DNA circulating in the blood.
  • Recommended only for individuals who decline or do not complete preferred screening tests.
  • These tests have lower sensitivity for advanced precancerous lesions and early‑stage cancers compared to stool‑based tests, meaning they may be less effective at preventing cancer or catching it early.

Dr. Pigazzi notes that these new options may require more physician guidance.

“Physicians will need to spend more time educating patients about the strengths and limitations of each screening option,” he says.

Since any positive blood or stool test must be followed by a colonoscopy, “there is potential for increased demand for endoscopy services.”

How Will Insurance Respond?

Insurance coverage often follows national guidelines, but gaps in coverage remain,  especially for younger adults.

“Under the Affordable Care Act, private insurers must cover USPSTF A- and B-rated screening tests without cost-sharing. The USPSTF currently gives a B recommendation for screening ages 45–49, meaning most private plans must cover screening starting at 45 with no copay. However, the USPSTF has not yet issued a recommendation specifically for blood-based tests, which could affect coverage mandates,” Dr. Robbins said.

Colorectal cancer is rising in people under 45, yet many still face coverage barriers even when they have symptoms or a family history.

“Some patients under the routine screening age may face barriers when seeking evaluation,” Dr. Pigazzi explains.

“Concerns about cost or coverage may delay diagnosis and contribute to more advanced‑stage presentations,” Dr. Pigazzi adds.

Despite the expanded menu of screening options, both Dr. Pigazzi and Dr. Cologne emphasize that colonoscopy remains the gold standard.

What Goes Into a Colonoscopy and How Patients Should Prepare

A colonoscopy is a procedure doctors use to screen for colon cancer by looking inside the colon.

This procedure requires your colon to be “cleaned out.” To clear out your colon, your doctor will prescribe a “bowel prep,” a liquid you drink the night before the procedure. The prep acts as a laxative that causes you to have multiple loose stools before your procedure.

Once your colon is cleared out, the gastroenterologist performing the procedure can have a clear look to evaluate if any polyps or masses are present.

Depending on the size and number of polyps found, it is recommended that patients undergo a repeat colonoscopy within three to five years.

Dr. Zuri Murrell is a colorectal cancer surgeon and Director of the Cedars-Sinai Colorectal Cancer Center, and he explains that when surgeons detect polyps, they “put a wire through with a little bit of a flange at the end, and we pull the polyp out.

Now, note there is no pain with that. Inside the colon, there are no pain fibers. So, there’s no pain.”

The advantage of a colonoscopy is that your doctor can remove any polyps found during the test. Many colon cancers can be caught on a colonoscopy before they develop or when the polyps are small enough to be removed without surgery.

A Growing Cohort of Younger Cancer Patients

Another layer to Dr. Lewis’ cancer diagnosis is the growing cohort of cancer patients younger than 50 being diagnosed, especially in the colorectal cancer sector.

“At the beginning of my career, there were really no patients under the age of 50,” Dr. John Marshall, director of the Ruesch Center for the Cure of Gastrointestinal Cancers at Georgetown University and Chief Medical Consultant at the Colorectal Cancer Alliance, told SurvivorNet.

“Now approximately half of my patients are under the age of 50.”

While colorectal cancer remains most common in people over 55, cases in younger adults have risen by 2.4% each year from 2012 to 2021, according to the American Cancer Society.

This surge prompted updated screening guidelines: average‑risk adults should now begin screening at 45 instead of 50, with earlier testing recommended for those with symptoms or a family history.

This change was recommended by advocacy organizations in 2018 and officially supported by the U.S. Preventive Services Task Force (USPSTF) in 2021.

The new recommendation led to more people getting screened earlier. Since 2018, there has been a 17% increase in colorectal cancer cases for people between the ages of 45 and 49, directly related to the new screening guideline.

WATCH: Deciding When to Operate on Colon Cancer

Researchers are still working to understand what’s driving the rise in younger patients.

Dr. Marshall believes the answer may lie in the gut microbiome — the community of bacteria, viruses, and other microorganisms in the digestive tract. Potential influences include diet, microplastics, and antibiotic exposure, but more research is needed to pinpoint the cause.

Colon Cancer Warning Signs

The most poignant signature of colon cancer is a change in bowel habits. Changes in the size or shape of bowel movements may cause constipation or diarrhea. A change in stool color, particularly black or tarry stools, can indicate bleeding from a tumor deep in the colon.

WATCH: Colon cancer symptoms.

Other symptoms can be harder to pinpoint, such as abdominal pain and unintentional weight loss. Finally, some tumors bleed a small amount over a long period, resulting in anemia (low red blood cell count) that is picked up on blood work.

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