Bowel cancer

What is bowel cancer?

Bowel cancer is cancer of the colon or rectum. Scientists often refer to bowel cancer as colorectal cancer.

The bowel is part of the digestive system and it’s divided into 2 parts: the small bowel and the large bowel. Nearly all bowel cancers are found in the large bowel, which is made up of the colon and the rectum.

Most of the nutrients from the food we eat are absorbed in the small bowel. Food then passes into the colon where water and any remaining nutrients are absorbed, leaving behind solid waste products. These waste products then move through the colon and the rectum before leaving the body.

The colon contains many types of bacteria, which have potentially important functions. The colon is lined with mucous membranes and contains cells that form part of the body’s immune defence.

Bowel cancer starts when cells in the bowel lining are damaged and grow uncontrollably, forming a tumour.

How common is bowel cancer?

Bowel cancer is the 3rd most common cancer in the UK (2021 data), with around 137 new cases diagnosed every day, and the 3rd most common in the world (2022 data). It is more commonly diagnosed in people over 50.

Men

Bowel cancer is the 2nd most common cancer in men in the UK, and the 3rd most common in men globally.

Women

Bowel cancer is the 3rd most common cancer in women in the UK, and the 3rd most common in women globally.