IBD & Colorectal Cancer
Each year in the U.S., 147,000 new cases of colorectal cancer (CRC) are diagnosed and more than 57,000 people die from the disease making it the second- leading cause of cancer-related deaths in this country. While these statistics are scary, keep in mind that most people with Crohn's or ulcerative colitis will not develop CRC. What's more, despite the risk factors, CRC is highly treatable in the early stages. That's why regular screenings and early detection are crucial.
What is the connection between Crohn's disease/ulcerative colitis and colorectal cancer?
Crohn's disease and ulcerative colitis, collectively known as inflammatory bowel diseases (IBD), are chronic diseases that cause inflammation in the digestive or gastrointestinal (GI) system. Specifically, ulcerative colitis causes inflammation in the lining of the colon, or large intestine, while Crohn's disease can cause inflammation in any part of the GI tract, from mouth to anus, including, in some cases, the colon.
If you have chronic inflammation of the colon, you are at a higher risk for developing CRC than the general population (unless your inflammation is limited to the very bottom of the rectum).
If your Crohn's disease is limited to the small intestine, you are at a slightly increased risk for cancer in the areas that are involved. Even if your disease is in remission, you remain at risk.
Two of the main factors associated with increased cancer risk are disease duration and the extent of the colon involved. The risk for CRC doesn't start increasing until 8 to 10 years after you develop Crohn's disease or ulcerative colitis. People whose entire colon is involved have the greatest risk, and those with inflammation that only involves the rectum have the lowest risk.
Finally, a rare complication of IBD is a chronic liver disease known as primary sclerosing cholangitis (PSC), which causes inflammation of the ducts that drain the liver. If you have either PSC or a family history of CRC, you may have a higher risk of developing CRC before the 8- to-10-year period.
It is important that you speak to your physician about when your screenings should begin. Knowledge of the IBD-CRC connection, along with annual screenings, may lead to early diagnosis and treatment, which can help reduce the potential life-threatening consequences of CRC.
What are some of the common signs and symptoms of CRC?
Some of the symptoms below, such as diarrhea or rectal bleeding, can be early warning signs of CRC in the general population. But they are difficult to assess in people with Crohn’s or ulcerative colitis, because they may represent a flare-up of IBD. If you are experiencing any of these symptoms, speak to your doctor:
- Change in the frequency of bowel movements
- Diarrhea, constipation, or feeling that the bowel does not empty completely
- Bright red or very dark blood in the stool
- Stools that are narrower than usual
- General stomach discomfort like frequent gas pains, bloating, fullness and/or cramps
- Weight loss with no known reason
- Constant fatigue
How is CRC diagnosed?
The best way for doctors to detect early signs of cancer in people with IBD is to
perform a colonoscopy. This screening tool makes it possible for doctors to determine
how much colitis is in the colon and the level of inflammation, and to find out
if there are any cancerous or precancerous changes on random biopsies or in bumps
If I have IBD, how often should I be screened or get a colonoscopy?
CRC risk applies to patients with active or inactive IBD. CRC risk also depends on the length of time a person has had IBD, as well as the condition of the colon. That is why it's important to see your doctor for routine colonoscopy every one to two years once you have had ulcerative colitis or Crohn's disease involving the colon for 8-10 years.
How can I decrease my risk for developing CRC?
The following may help you reduce the risk of colorectal cancer:
- If you have been diagnosed with Crohn’s disease or ulcerative colitis, see your gastroenterologist annually for a general checkup, regardless of how healthy you feel.
- Discuss any concerns you may have with your doctor.
- Report any changes in symptoms.
- Help keep your disease under control by staying on your medications, even when you’re feeling well.
- You and your doctor should review the medications you are currently taking.
- Update your doctor on family history for colorectal cancer.
- Early detection is critical to reducing your risk for CRC.
- Exercise and eat a healthy diet.
- As a preventative measure, your doctor may suggest you take medications like sulfasalazine or mesalamine, which help control the inflammation of IBD and may also reduce the risk for developing CRC.
Use our CRC Risk Factor Discussion Guide to help you and your doctor assess your individual risk of CRC. Download