Menu

Crohn's and Colon Cancer: What's the Link?

Medically Reviewed by Laura J. Martin, MD on October 14, 2020

If you have Crohn’s disease, you may need to get checked more often for early signs of colon cancer. But most people with Crohn's don’t get colon cancer, and there are things you can do to lower your risk.

The two keys are to keep your Crohn’s under good control and to keep up with your colon cancer tests. Ask your gastroenterologist how often you should get a colonoscopy. The general recommendation is that people who've had Crohn's disease for at least 8 years should get this test every 1-2 years.

What the Research Shows

Findings on this are mixed. Some studies have found that people with Crohn's aren't more likely than anyone else to develop cancer. But other research has reached the opposite conclusion, showing a substantially higher risk.

Inflammation is one of the ways the two conditions may be linked. Crohn's causes high levels of inflammation in the intestines. That inflammation, in turn, may make it more likely that abnormal cells that could become cancerous could develop in the GI tract.

What Raises the Risk

How long you’ve had Crohn’s. Most experts agree that the danger goes up the longer you've had Crohn’s. One meta-analysis (in which researchers crunch data from several earlier studies) showed that about 3% of people who've been living with Crohn's for 10 years developed colon cancer. That number rose to about 8% for those who had Crohn's for 30 years.

In comparison, the odds of developing colon cancer at some point in your life -- what researchers call the average lifetime risk of colon cancer for the general population -- is about 4%.

Liver complication. People with inflammatory bowel disease (IBD), including Crohn's, almost certainly have an increased risk of colon cancer if they've develop an IBD liver complication called primary sclerosing cholangitis.

Colon cancer also seems to be more dangerous for people with Crohn's disease. One recently published study from Sweden found that people with Crohn's who get colon cancer are more likely than other colon cancer patients to die from it.

Lower Your Colon Cancer Risk

There are several ways to help protect yourself from colon cancer if you have Crohn’s disease.

Work closely with your gastroenterologist to manage your Crohn’s. You want it to be as well-controlled as possible. Seeing your doctor regularly and taking your medications as prescribed will help keep inflammation in your gut in check.

Keep up with your health screenings. Colon cancer is most treatable when it's caught early, and getting regular colonoscopies is the best way to do that. Doctors are often able to remove precancerous polyps during this procedure, which means that it's sometimes possible to stop this cancer before it even starts.

Getting regular colonoscopies may reduce your chances of getting colon cancer. A large study of nearly 7,000 people with IBD found that those who had a colonoscopy within the past 3 years were less likely to develop colorectal cancer. The same research found that frequent colonoscopies may save your life even if you do get cancer: People with IBD who had a colonoscopy within 6-36 months before being diagnosed with cancer were less likely to die from it.

Ask your gastroenterologist if you'd benefit from including chromoendoscopy in the procedure. This means that blue dye will be sprayed into your colon during the colonoscopy. The color helps your doctor spot flat, precancerous lesions that might otherwise be difficult to see.

Reduce other risks. Curb other risk factors as much as possible. For instance:

  • Be physically active.
  • Keep your weight in a healthy range.
  • Include lots of vegetables, whole grains, and fruit in your diet -- and limit red meat and processed meats.
  • Avoid alcohol or limit it to no more than one drink a day for women and up to two drinks a day for men.
  • Don’t smoke.

 

WebMD Medical Reference

Sources

SOURCES:

Clinical Gastroenterology and Hepatology: "Colonoscopy is associated with a reduced risk for colon cancer and mortality in patients with inflammatory bowel diseases."

Crohn's & Colitis Foundation: "The Risk of Colorectal Cancer in Crohn’s Disease and Ulcerative Colitis Patients."

Fox Chase Cancer Center at Temple University: "Inflammatory Bowel Disease and Colorectal Cancer Risk: Understanding the Link."

Medscape: "Crohn Disease Questions and Answers," July 2019.

National Cancer Institute: "Cancer Stat Facts: Colorectal Cancer."

The Lancet Gastroenterology & Hepatology: "Colorectal cancer in Crohn's disease: a Scandinavian population-based cohort study."

© 2020 WebMD, LLC. All rights reserved.