Paul O' Rourke's sons, wife, and parents visit him during his inpatient stay at Johns Hopkins Hospital after his partial colectomy.
CNN  — 

An unexplained rise in colorectal cancer rates among younger adults is leading more people – including physicians – to get screened for the disease early, sometimes far ahead of the recommended age of 45 for those at average risk.

Scientists racing to find clues toward understanding why cases of colorectal cancer are climbing among younger people. Some suspect factors driving this increase are environmental, while others wonder if they are dietary.

One new study, to be presented at the annual meeting of the American Society of Clinical Oncology in June, suggests that a young adult’s microbiome – the collection of microbes, such as bacteria, fungi and viruses that naturally live in human bodies – may play a role.

The research has not yet been peer-reviewed or published in a medical journal, but an abstract posted online describes how researchers analyzed data on 36 colorectal cancer patients who were diagnosed before the age of 45 and 27 patients who were diagnosed after the age of 65. The researchers found “significant differences” in the bacterial and fungal species detected in the microbiomes of the younger patients versus the older patients, which they wrote, warrants “larger, prospective studies to elucidate the role the intratumoral microbiome plays” in developing cancer.

As the search for answers continues, some younger adults in the United States have sought colorectal cancer screenings at a time when the disease is on the rise for their age group. But there is also concern that this trend could lead to the overuse of colonoscopies.

‘I was really lucky’

As the email marketing coordinator for the Colorectal Cancer Alliance, Francesca Arminio, based in Washington, DC, knew the effects this disease was having on people around her age.

Last year, when she started having symptoms that are common in people with colorectal cancer, she began tracking her experience. Such symptoms can include a change in bowel habits, blood in the stool, abdominal pain and unexpected weight loss.

Francesca Arminio

Arminio had blood in her stool and constipation. She immediately talked to her doctor about a colonoscopy, although she worried that she might meet some resistance because she was 33.

She was ready to be her own advocate, she said, and to fight for a colonoscopy. To her surprise, Arminio’s doctor agreed that she needed one.

“I was really lucky,” she said. “My doctor, after asking me a myriad of questions, was like, ‘We’re going to get you a colonoscopy,’ and I was like, ‘Thank you.’ “

During her 30- to 45-minute procedure, the medical team found three polyps, one of which was concerning and classified as “aggressive,” Arminio said, adding that it could have developed into cancer within the next few years. The polyps were removed, and she recovered quickly.

Arminio plans to get a colonoscopy every three years.

That’s typical for people who had certain types of polyps removed during a colonoscopy, according to the American Cancer Society. Anyone who is not at risk for colorectal cancer may be told to get a colonoscopy every 10 years.

“If I didn’t work at the alliance and didn’t know the information that I do, I probably wouldn’t have gotten screened,” she said. “I was fully in there with boxing gloves, ready to go for it and advocate for myself, but I was super lucky – but that’s not always the case.”

Cases have been increasing among people younger than 45 since the mid-1990s. The absolute risk remains low among ages younger than 45, but the proportion of cases that are in that age group increased from 3.7% in 1995 to 5.8% in 2019, according to the American Cancer Society. The incidence rate increased 55%, from 2.9 to 4.5 per 100,000 people.

Colorectal cancer screening rates increased in the United States from January 2018 through December 2022, largely because of an increase in screenings among 45- to 49-year-olds, according to data published in March in the journal Epic Research, which is owned by the health care software company Epic.

Francis Levandowski III

Family nurse practitioner Francis Levandowski III, 33, chose to get a colonoscopy after having similar symptoms to Arminio’s, including rectal bleeding.

“I knew that was a problem, so I needed to find a doctor,” said Levandowski, who’s based in Phoenix.

In his case, there were no signs of cancer, but the procedure did turn up another common, treatable problem: hemorrhoids.

Levandowski not only has a personal family history of cancer, he has seen young adult patients die from it. He thinks the recommendation for when to start getting colonoscopies should be lowered even more to avoid cases that may go undetected.

In the United States, “colon cancer is the fourth most common cancer. It’s one of the most preventable with the colonoscopy,” he said. “I am all for lowering the age range, because we are seeing patients at younger ages have advanced disease sooner.”


The American Cancer Society emphasizes that its guidelines to start screening at age 45 are for people of average risk; individual patients and their doctors may decide it makes sense to screen early.

The US Preventive Services Task Force – a group of independent medical experts whose recommendations help guide doctors’ decisions – recommends screening for colorectal cancer in adults starting at age 45. But that’s a recent shift.

The task force lowered the recommended age from 50 in 2021, a change that required private insurance and Medicare to cover the costs of screening for the expanded age group, per the Affordable Care Act, Epic said in the study.

That recommendation is for asymptomatic people of average risk – but no matter a person’s age, they should talk to their doctor about screening if they notice blood in their stool or a change in their bowel habits.

Still, doctors can be leery of offering colonoscopies to young adults, said Dr. William Dahut, chief scientific officer at the American Cancer society.

One is logistical: If more people want a colonoscopy, it’s possible that some people who need the procedure won’t be able to get it.

“If you have folks where the likelihood of finding cancer is quite low undergoing screening tests, the overall benefit for the population would be small, and that does run into logistical issues,” Dahut said.

There is also concern that some people in their 40s who are recommended to get screened for colorectal cancer are not doing so, said Dr. Dionne Ibekie, an anesthesiologist in central Illinois.

“Unfortunately, the guidelines are not being universally practiced,” Ibekie said. “The guidelines changed that screening needs to start at 45. Unfortunately, though, patients are still getting screened at age 50-plus.”

Understanding your risk

Ibekie has also seen a rise in younger people diagnosed with colon cancer, and an increasing portion of them have been diagnosed at advanced stages of the disease.

“It’s concerning because I see it at both ends,” said Ibekie, who has talked about the rise in colorectal cancer cases on her podcast “The Ivy Drip.” The most recent patient she saw with advanced colon cancer was 28 years old.

Dionne Ibekie

Ibekie, who turns 38 this year, had a colonoscopy at age 35.

She has always struggled with her gastrointestinal health, and when she started to have symptoms similar to those of colorectal cancer, she called her primary care physician, who referred her to a gastroenterologist, who ordered a colonoscopy. She did not have cancer.

Ibekie often wonders whether her experience seeking a colonoscopy would have been different if she weren’t a doctor who was already in tune with how the medical system works and how to advocate for herself.

“I have to admit my own privilege because I am a physician. So I know these risk factors. I know that as an African American, I’m at higher risk for getting colon cancer at a younger age and having a more aggressive form,” she said. “And I also know that the symptoms that I was experiencing could be signs of something that could be malignant.”

Colorectal cancer disproportionately affects the Black community, as Black people are about 20% more likely to get the disease and about 40% more likely to die from it compared with most other racial or ethnic groups, according to the American Cancer Society.

Ibekie said she would encourage her physician colleagues to have conversations about colorectal cancer symptoms with their patients who are at an increased risk for the disease – especially their Black patients.

‘The bigger barrier’

Still, it’s not uncommon for younger people without a family history to have to advocate strongly for a colonoscopy when they have symptoms, said Dr. Bethany Malone, a colon and rectal surgeon in Fort Worth, who plans to get a colonoscopy this year. She is 36.

“A lot of the patients who have no family history I’ve seen, they’ve really had to advocate for themselves, which I hate as a health care provider. I feel like our job should be to help our patients figure things out,” she said.

Malone said that possibly lowering the recommended age for average-risk patients is only part of the equation needed to catch cancer earlier. The other half: lowering out-of-pocket costs for diagnostic colonoscopies, a procedure that can often cost around $1,400, which she described as “the bigger barrier.”

“If insurance companies could cover a bigger chunk of that, then more people who have indications for a colonoscopy would actually get them,” she said.

“I don’t find necessarily the screening age to be the bigger prohibitive factor. I think it’s the out-of-pocket costs for diagnostic colonoscopy. So for anyone under the age of 45, you’re getting diagnosed with a diagnostic colonoscopy, meaning there’s some type of symptom that triggered the colonoscopy,” Malone said. “Most insurance companies really don’t cover those to a high extent.”

One insurance company, UnitedHealthcare, has announced that starting in June, members with commercial plans seeking gastroenterology endoscopy services – including colonoscopies – will be required to have “prior authorizations” for those services.

The prior authorization – meaning the insurer will need to preapprove the procedure or the enrollee pays out of pocket – is valid for 90 calendar days. Although colonoscopy procedures for routine screenings are not included in that new requirement, surveillance and diagnostic procedures to detect cancer are.

UnitedHealthCare said in a fact sheet that this change is due to colonoscopies being overutilized.

“It is part of our mission to help ensure our members get the care they need, which is supported by the most up-to-date clinical evidence to ensure the appropriate course for patient diagnosis and treatment. Not following established clinical evidence for gastrointestinal endoscopy procedures can lead to negative outcomes for your patients and our members,” the fact sheet says.

“In recent years, studies have shown evidence that overutilization of invasive non-screening (surveillance and diagnostic) colonoscopy, EGD and capsule endoscopy procedures in certain situations exposes patients to unnecessary risks and costs,” it says. “The gastrointestinal endoscopy prior authorization program is designed to help ensure the care our members receive is safe, effective and affordable.”

Some gastroenterologists are concerned about the prior authorization policy.

“What concerns me is that it makes it challenging for the provider to make a decision quickly and to go ahead, do a procedure if necessary. I might have to wait a week or two weeks or three weeks for prior authorization,” said Dr. Joel Gabre of Columbia University Irving Medical Center.

According to UnitedHealthCare’s website, a decision on a request for prior authorization for medical services will typically be made within 72 hours of receiving the request for “urgent cases” or 15 days for “non-urgent cases,” but those timeframes may vary by state.

“For some patients, that may not change their course. In other patients, especially if they have blood in their stool and there is concern they have colon cancer. This may cause a delay in making a diagnosis and then referral to an oncologist,” Gabre said, referring to the timing described on UnitedHealthCare’s website.

“At least patients who are age 45 will be able to get their screening procedure. But if someone’s younger than 45 and has symptoms, then there may be a delay in their care,” he said, adding that such prior authorization policies “create a barrier” to getting colonoscopies and other endoscopic procedures.

In an emailed statement Friday, a spokesperson for UnitedHealthCare said, “Our electronic submission process allows for immediate approvals for physicians who have a history of following evidence-based guidelines for the requested procedure. For procedures that do not receive immediate approval, decisions are typically made within two business days after receipt of all required clinical information needed for our GI specialists to review the case – well within the average wait time to schedule a service included in this policy.”

Malone, who works in private practice, travels to different facilities to provide care for her patients and for those who are paying out of pocket, she starts by calling around to find the cheapest one.

“For some of them, it’s cheaper to not run it through insurance and pay completely out-of-pocket,” Malone said.

The issue of cost is complicated by what screening guidelines recommend, Ibekie said. She thinks screening guidelines should recommend that African Americans start colorectal cancer screenings at age 40 because of their higher risk for the disease, which could then lead to insurance companies covering the procedure for younger ages.

“Insurance is not going to cover it if it’s not in the guidelines,” Ibekie said. “If there’s no indication or formalized guideline, then you won’t get coverage, and many patients can’t afford to pay for that kind of exam out-of-pocket.”

An unexpected diagnosis

Dr. Paul O’Rourke, 39, made the sudden switch from physician to patient last fall.

“It was unexpected,” said O’Rourke, an assistant professor of medicine at the Johns Hopkins University School of Medicine, where he co-directs the Medical Education Pathway program.

It was around the beginning of 2022 when O’Rourke started noticing small amounts of blood in his stool. He has no family colorectal cancer history, and he is under 45, which led him to think the symptoms were not a cause for concern.

“I thought there were more common things that would be the cause, like internal hemorrhoids,” said O’Rourke, who is also the associate program director of the internal medicine residency program at Johns Hopkins Bayview Medical Center.

Then he noticed that the symptoms were happening more frequently.

He decided to see a doctor. The doctor thought it was unlikely O’Rourke’s symptoms were due to cancer, but the symptoms continued to progress.

O’Rourke’s wife, a primary care physician, pushed him to get screened.

“As soon as I was done with the colonoscopy, it was very evident pretty soon that things were not all right,” O’Rourke said.

A tumor mass had been found in his upper rectum. O’Rourke said the next few weeks brought severe uncertainty and fear.

“The predominant fear that really went through my mind was, I have two young boys – a 7-year-old and a 3½-year-old – and my wife and just worrying about being there for them,” O’Rourke said.

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O’Rourke was diagnosed with stage II colorectal cancer and had surgery on November 18. But about two weeks later, he had a “pleasant surprise.”

He was told the cancer was isolated to one area and was not as invasive as previously thought. He was reclassified to stage I and told that he did not need additional treatment and would need only to monitor his health.

O’Rourke said that he now advocates for more awareness for the increasing incidence of colorectal cancer among younger adults and the role screening can play.

“I think the screening strategies need to be individualized to every patient,” he said. “The current recommendations are that average-risk colorectal cancer screening should be offered to all patients at the age of 45. However, I think every individual is unique and different, and that needs to be characterized by his or her primary care physician.”