Ulcerative Colitis and Colon Cancer: Risks, Screenings, and More

UC causes inflammation that can eventually turn cells lining the colon into cancerous cells.

People with UC are more than twice as likely to get colorectal cancer as those without the disease, according to a 2012 review.

According to a 2008 review of scientific literature, the likelihood of getting colorectal cancer was:

• 2 percent after living with UC for 10 years
• 8 percent after 20 years
• 18 percent after 30 years

By comparison, the American Cancer Society (ACS) states that the overall risk of any American getting colorectal cancer is less than 5 percent.

However, more recent research shows that colorectal cancer rates are dropping among people with inflammatory bowel diseases (IBDs) such as UC.

Duration of ulcerative colitis

Your risk for colon cancer typically starts to increase once you’ve lived with UC for about 8 to 10 years, according to the Crohn’s & Colitis Foundation. The longer you have UC, the higher your cancer risk.

According to a 2019 literature review, colorectal cancer rates for people in North America increase dramatically after a person has lived with UC for 30 years.

Colorectal cancer rates in Asia increase dramatically after a UC duration of 10 to 20 years. Cancer rates for Asian people who’ve had UC for 10 to 20 years were four times higher than rates for Asian people who’ve had UC for 1 to 9 years.

Cancer rates for Europeans also increased as UC duration increased. However, the increase in cancer rates over time wasn’t considered statistically significant. There wasn’t enough data from Oceania to compare cancer rates over time.

This literature review had some noteworthy limitations. For instance, data wasn’t included for people who’d had colorectal polyps (abnormal tissue growths) or a colectomy for UC.

Data for people with cancer outside of the colon or rectum, or those with a family history of colorectal cancer, was also excluded.

Inflammation

How much of your colon inflammation affects also factors into your risk for getting colorectal cancer.

People with a lot of inflammation in their entire colon are at the highest risk for colorectal cancer. Those with inflammation only in their rectum are at the lowest risk.

Primary sclerosing cholangitis (PSC)

You also need to be prepared if you have primary sclerosing cholangitis (PSC), a rare complication of UC. PSC affects the bile ducts, which carry digestive fluid from the liver to the intestine.

PSC causes inflammation and scarring that narrows the ducts. It also increases the risk of colorectal cancer, and the disease may start sooner than 8 to 10 years after you’re diagnosed with UC.

Because your risk for colorectal cancer increases over time if you have UC, it’s important to receive regular screenings for colorectal cancer.

People with UC should talk to their doctors about getting a colonoscopy, the main test used to detect this cancer.

Getting regular colonoscopies can help lower your risk for developing colorectal cancer or dying from colorectal cancer.

For people with IBDs who underwent regular screenings, the odds of developing colorectal cancer dropped by 42 percent. The odds of dying from the cancer dropped by 64 percent.

How a colonoscopy works

In a colonoscopy, a doctor uses a long, flexible tube with a camera at the end to see inside your colon. The test helps them detect polyps in your colon lining. The doctor can remove these growths to prevent them from turning into cancer.

Your doctor might also remove tissue samples during your colonoscopy and have them tested for cancer. This procedure is called a biopsy.

How often to screen

Ask your doctor about starting to get regular colonoscopies if it’s been 8 years since your symptoms first appeared or you were diagnosed with UC.

People with UC are generally advised to have a colonoscopy every 1 to 3 years. Some people may need to have this test more or less often based on factors such as:

• the age when they were diagnosed
• how much inflammation they have and how much of their colon it affects
• their family history of colorectal cancer
• whether they also have PSC

Here are a few other things you can do to lower your chances of developing colorectal cancer and improve your odds of finding it early if you develop it:

• Ask your doctor about taking medications such as sulfasalazine (Azulfidine), vedolizumab (Entyvio), or mesalamine (Asacol HD, Pentasa). These drugs help manage UC, and they may help lower your risk for colorectal cancer.
• Take your medications as your doctor prescribed to keep your UC inflammation well managed.
• See your gastroenterologist for check-ups at least once a year.
• Let your doctor know if any of your family members had colorectal cancer or have recently been diagnosed.
• Eat more fruits, vegetables, and whole grains such as brown rice or wheat bread.
• Limit red meat, such as burgers, steaks, and pork. Also limit processed meats, such as hot dogs, bacon, and sausage. They’ve been linked to colorectal cancer risk.
• Avoid alcohol or limit yourself to no more than one drink a day.
• Try to walk, ride a bike, or do other exercises on most days of the week.

Along with getting regular screenings, look for these symptoms of colorectal cancer and report them to your doctor right away:

• a change in your bowel movements
• blood in your stool
• stools that are thinner than usual
• excess gas
• a feeling of bloating or fullness
• diarrhea or constipation
• unplanned weight loss
• more fatigue than usual
• vomiting

Read this article in Spanish.