Bowel cancer: who’s at risk, the symptoms to watch out for, and how to get tested

Bowel cancer is a general term for cancer that begins in the large bowel, which is made up of the colon and the rectum. It is sometimes called colorectal cancer. Nearly 43,000 people are diagnosed in the UK each year, making it the fourth most common cancer and the second-biggest cancer killer.

At an early stage, bowel cancers are one of the easiest to identify and treat, says Prof Sina Dorudi, a consultant colorectal surgeon at the Princess Grace Hospital, part of HCA Healthcare UK. She explains, “The cancer usually starts as benign polyps which grow on the wall of the bowel. If these aren’t spotted, then certain types can turn cancerous and develop into a tumour. It is important to emphasise that if the tumour is caught early, in most cases it can be removed in full, with surgery.”

In August, National Institute for Health and Care Excellence (Nice) recognised the importance of early screening. They announced that £5 home screening tests – already offered to older adults as part of screening for bowel cancer – should now be offered routinely to those with possible symptoms of disease.

Nice said the changes should mean around 100,000 fewer people a year having to undergo colonoscopies, an invasive procedure to rule out cancer in the bowel, colon or rectum.

Read on for the basics about the disease.

Who is at risk of bowel cancer?

Put simply, “anyone could be at risk,” says Genevieve Edwards, the chief executive of Bowel Cancer UK. “Bowel cancer is more common in people who are over 50. But younger people can and do get diagnosed with it, too. So really, anyone with any symptoms that are concerning – the ‘red flag’ symptoms – should go and talk to their GP.”

More than nine in 10 cases of bowel cancer are diagnosed in people aged 50-plus. However, cases in younger people are rising: around 2,500 cases are diagnosed in under-50s each year. If you have a first-degree relative (a parent, sibling, son or daughter) who was diagnosed with bowel cancer, this increases your risk.

There are other lifestyle factors that can increase your risk of developing the disease; in fact, 54 per cent of cases are thought to be preventable. Obesity is a key risk factor, responsible for around 11 per cent of bowel cancer cases in the UK. A poor diet also raises your risk: studies have shown that eating too much red or processed meat causes around 13 per cent of cases, according to Cancer Research UK. The World Health Organization ranks bacon, ham and sausages up with cigarettes as a major cause of cancer.

A diet rich in fibre reduces your risk, and eating too little fibre is linked to 30 per cent of bowel cancer cases. Drinking alcohol and smoking are both risk factors, responsible for 6 and 7 per cent of cases respectively.

What is the survival rate?

Bowel cancer is curable if it is caught early; 97 per cent of people survive bowel cancer diagnosed at stage 1, says Edwards. Survival rates drop with each stage of the disease: according to Cancer Research, only 10 per cent of people with stage 4 bowel cancer will survive their cancer for five years or more after they’re diagnosed, unless it has spread into the liver and a surgeon can remove it, in which case the survival rate rises to 40 per cent.

What are the symptoms of bowel cancer?

The “red flag” symptoms of bowel cancer are: bleeding from your bottom or blood in your stool; a persistent and unexplained change in bowel habit; unexplained weight loss; extreme tiredness for no reason; and a pain or lump in your tummy.

“Most people with these symptoms don’t have bowel cancer, but if it is bowel cancer, you need to get diagnosed as quickly as possible,” says Edwards. “It’s treatable if it’s diagnosed early, so if you go straight to your GP, rule out bowel cancer first and fast. And if it is bowel cancer, of course, the earlier you’re diagnosed, the more likely it is that you can be successfully treated.”

How do you screen for bowel cancer?

Bowel cancer screening is currently available to everyone aged between 60-74 (this is being reduced to age 50 by 2026 : Nice has also announced that anyone with symptoms should now be able to get them). Everyone in this age group who is registered with a GP will be automatically sent a screening kit every two years. In Scotland, screening already starts at age 50.

“You’ll get sent a straightforward home test, called a FIT test [faecal immunochemical test]. It looks for tiny amounts of blood in your stool,” says Edwards. “If it’s there, then they’ll refer you for diagnostic tests. And the majority of people who go on for those diagnostic tests don’t have bowel cancer. So it’s a really easy screening test to do.” You will automatically be offered screening if you’re in the relevant age bracket, but anyone of any age with symptoms of bowel cancer can now ask their GP for a FIT test, says Edwards.

“People who are under the age of 50 often struggled to get a diagnosis in the past, because GPs will investigate other things first – and that’s completely reasonable, because in most cases it really will be something else,” she says. “But now that we’ve got this home test that the younger people can ask for, it should speed up diagnosis for them, too. Which is really important.”