Bowel cancer and cystic fibrosis

The latest research shows that CF is linked to an increased risk of bowel (or colorectal) cancer. Read more about what bowel cancer is, the risk for people with CF and what screening involves.

What is bowel cancer?

Bowel cancer, also called colorectal cancer, affects the large bowel, which is made up of the colon and rectum.

In people who don’t have CF in the UK, bowel cancer is the fourth most common cancer. Most people diagnosed with bowel cancer are over 50 and over half are over 70.

In England, Wales and Northern Ireland, people over the age of 60 are invited to take part in bowel cancer screening. In Scotland, people are invited to take part in screening from the age of 50.

To find out more about bowel cancer, visit Bowel Cancer UK’s website.

If you are worried about your health, or experiencing any unusual bowel habits, always speak to your CF team.

What is the risk of developing bowel cancer in people with cystic fibrosis?

The latest research found that people with CF are five times more likely to develop bowel cancer than people without, and that the overall rate of CFTR mutations in the bowel cancer population was a lot higher than was expected. However, it is very important to note that the risk of an individual with CF developing bowel cancer remains low. Between 2009 and 2020 there were just 28 cases of bowel cancer in people with CF in the United Kingdom. 

At this stage, we do not know what will happen to the number of cases of bowel cancer. Due to effects of modulators, this could go down, but we could also see rates increase as the age of the CF population goes up.

The study found that people with CF and bowel cancer had an average age of diagnosis of 52 years, which is significantly younger than in people without CF, which is an average of 73 years.

The study is in agreement with studies from other countries and shows that CF is linked to an increased risk of bowel cancer. It also shows, in the control population studied, that the rate of CFTR mutations in the bowel cancer population is higher than would be expected.

It is not known why people with CF might have an increased risk of developing bowel cancer. The Trust is funding a Strategic Research Centre to investigate whether there is an increased risk in people with CF and why this might be, so that CF teams can understand how best to treat their patients.

How are people with CF screened for bowel cancer?

Further work is needed to determine whether people with CF would benefit from a tailored screening programme and what form it should take. More research is needed to understand the role of CFTR gene mutations in the development of GI cancer, for people with CF and those without.

Some CF centres offer screening for bowel cancer from the age of 30 to people who want it. Screening can be performed through two different tests:

  • Faecal immunochemical test (FIT) – This test is performed at home and is done by taking a small poo sample.
  • Colonoscopy – For this test, a tube is inserted through your back passage. It has a light and a tiny camera on it that allows the person doing the exam to see your bowel lining. During a colonoscopy, small cells called polyps might be removed at the same time. These are not dangerous, but can very rarely become cancerous which is why they are always removed.

There are some small risks associated with a colonoscopy, which will be explained to you if you are offered one.

If you have any questions about bowel cancer and cystic fibrosis, please speak to your CF team, or contact our Helpline.

Page last reviewed: January 2023
Next review due: January 2026

Your donation will make a difference:

Select amount
Select amount