By Daily Mail (U.S.) | Created at 2026-08-14 19:26:34 | Updated at 2026-08-14 21:41:04
4 hours ago
A chronic digestive condition suffered by about one in 400 Americans has been linked to an increased risk of a range of deadly cancers.
Crohn's disease, which causes debilitating abdominal pain, chronic diarrhea and exhaustion, is an incurable type of inflammatory bowel disease (IBD) that causes inflammation in the digestive tract and affects about a million Americans.
The chronic digestive condition has now been linked to a heightened risk of several cancers, according to a large Swedish study tracking nearly 40,000 patients over seven years.
The findings confirm that people with Crohn's face a higher cancer rate than the general population, regardless of whether they have treated their condition with immune-suppressing drugs.
That includes an elevated risk of blood cancers, as well as cancers of the lung, small bowel and the liver and bile ducts. The study also found a particularly strong link to skin cancers, especially squamous and basal cell carcinomas.
The increased risk is real but modest, at roughly one extra cancer per 1,000 patients annually, after excluding non-melanoma skin cancers.
That excess risk appears to be driven largely by the disease itself; specifically, the chronic inflammation it causes, rather than by the medications used to treat it.
Over time, that persistent inflammation can damage cell DNA, promote abnormal cell growth, and create an environment where tumors are more likely to develop.
An estimated 1 million people in the US are living with Crohn's disease, an incurable inflammatory bowel disease (stock image)
To get a clearer picture of cancer risk, the study, published in the American Journal of Gastroenterology, tracked nearly 39,000 Swedish Crohn’s patients diagnosed between 2007 and 2022 using national health databases that capture every diagnosis, prescription and outcome.
They then matched each Crohn’s patient with up to ten healthy people of the same age, sex and geographic location, creating a comparison group of more than 360,000 people without any type of IBD.
Matching ensures that any differences in cancer rates could be more confidently attributed to Crohn’s itself, rather than age, sex or where people live.
The researchers divided Crohn’s patients into groups based on their treatment history, including one consisting of people who had never taken immunosuppressive drugs – the standard treatment for Crohn’s.
The other group consisted of people who had taken immunosuppressive drugs such as thiopurines, Humira, vedolizumab or ustekinumab – or combinations of them.
They compared cancer rates between the two groups, calculating both how many extra cases occurred and how much higher the risk was for Crohn's patients
Then, they broke the data down by cancer type, by age group, including children under 18, and by treatment history to see where the risks were highest and where they weren't.
Over more than seven years of follow-up, the researchers confirmed that Crohn's patients do face a higher - albeit just slightly - cancer risk than the general population.
Throughout the 2010s, women consistently had higher rates of Crohn's than men, according to Medicaid data
The extra risk was most pronounced for skin cancers; specifically basal and squamous cell carcinomas, which affect 3.6 million and 1.8 million Americans each year, respectively, and have fatality rates of 0.12 percent and 4.3 percent when detected early.
Crohn's patients had a higher rate of these cancers compared to the general population.
For basal cell carcinoma, the rate was elevated by 1.05 to 1.58 extra cases per 1,000 person-years, while squamous cell carcinoma was elevated by 0.34 to 1.17 extra cases per 1,000 person-years.
But when researchers removed those skin cancers from the equation, the picture shifted.
After excluding non-melanoma skin cancers, Crohn's patients had about one extra cancer diagnosis per 1,000 people each year.
The excess was driven largely by lung cancer, small bowel cancer, cancers of the liver, gallbladder and bile ducts, and blood cancers like lymphoma. The study found no elevated risk for colorectal, breast or prostate cancers.
Even patients who never took these drugs had higher cancer rates than healthy individuals. That suggests the disease itself, not the treatments, is a major driver.
Crohn's disease is most common in middle-aged adults, with prevalence peaking between ages 40 and 60
For years, experts have understood that Crohn's cancer risk involves both the disease and the drugs used to treat it, but separating the two has always been difficult.
The likely reason is chronic inflammation, which over time can damage cells and raise the odds of cancer.
Blood cancer risk stood out as particularly elevated in Crohn's patients. Those who had used immunosuppressants such as Humira faced nearly three times the risk of lymphoma compared to healthy people, while those on thiopurines faced about 1.5 times the risk.
For hepatobiliary cancers, including those of the liver and bile ducts, the risk was also higher in Crohn's patients across the board, regardless of treatment.
Patients on vedolizumab and ustekinumab had the biggest relative increase in liver cancer risk, but because the actual number of cases was tiny, the real-world added danger for most patients remained very low.
The good news is that the study found no significant cancer increase in pediatric patients under 18, which may reassure younger patients and their families.
For adults, the risk increased with age, underscoring the importance of regular colonoscopies and full-body skin checks, particularly for older patients.
While Crohn's disease does increase cancer risk compared to the general population, the absolute risk remains low, meaning the vast majority of people with Crohn's will never develop these cancers.
The researchers noted several important limitations. The study’s follow-up time of just over seven years may be too short to capture cancers that can take decades to develop, meaning longer-term risks could be underestimated.
The researchers counted patients as 'treated' for the entire study once they started a drug – even if they later stopped – a conservative approach that may underestimate each medication's true risk.
By counting patients as treated even after they stopped the drug, the study mixes unexposed time into the treated group, which can hide or weaken a real cancer link and make the medication appear less risky than it actually is.
As an observational study, it tracked real-world data rather than a controlled experiment, so it could not fully rule out other factors like smoking and obesity.
Because the study was based in Sweden, which has a lower cancer rate than the US, the findings may not directly translate to American patients.
While the cancer risk associated with Crohn's is modest, the number of Americans living with the disease is substantial and growing.
A 2024 study tracked Crohn's disease rates in the Medicaid population – which encompasses about one in four Americans – from 2010 to 2019.
Among nearly 200,000 beneficiaries with the condition, prevalence more than tripled from 56 to 165 per 100,000, while new diagnoses declined from 18 to 13 per 100,000 person-years.
This divergence is significant. It means more Americans are living longer with a chronic condition that requires ongoing care, even as the rate of new cases slows, a pattern consistent with other Western countries.
