Bowel cancer symptoms and signs

Bowel cancer (also known as colorectal cancer) is an umbrella term given to a cancer that starts in the large bowel which includes the colon and the back passage (rectum). There are 44,100 cases diagnosed each year, making it the fourth most common cancer in the UK.¹

Mags Beal, Cancer Care clinical operations manager, looks at the most commonly asked questions around bowel cancer, from the symptoms to how to help prevent it.

What is bowel cancer?

Most cancers of the bowel start with small, benign growths that develop in the lining of the bowel. These can turn malignant over time if they aren’t treated. It can spread through the lymphatic system made up of lymph nodes, which are part of the body’s immune system. One of the first places bowel cancer spreads is to the lymph nodes in the tummy (abdomen).¹

Cancer Research UK state: “Bowel cancer can also spread to other parts of the body through the bloodstream. The liver is a common place for bowel cancer to spread because blood flows directly from the bowel to the liver. The cancer can also spread to the lungs or rarely other organs.”

If it is caught early, then bowel cancer has a high survival rate. When diagnosed in its earliest stage, 92% of people with bowel cancer will survive their disease for five years or more, compared to only 10% of people who are diagnosed at the latest stage.²

What are the symptoms of bowel cancer?

The main symptoms of bowel cancer are:

• bleeding from your bottom and/or blood in your poo (please do look),
• a change in bowel habit lasting for 3 weeks or more, especially to looser or runny poo,
• unexplained weight loss or loss of appetite,
• extreme tiredness for no obvious reason or shortness of breath,
• a pain in your tummy, or a lump in your tummy.³

Tiredness and breathlessness may seem surprising but these can be symptoms of anaemia. Anaemia can occur due to loss of blood from a bowel tumour, so it can be an initial symptom of bowel cancer.

You may get one, some, or all of the above symptoms. None of these symptoms mean you have bowel cancer, but you should see your doctor to get them checked out.

The most important thing is to know what is normal for you, and if you notice any changes, see your doctor.

Who does bowel cancer most commonly affect?

Bowel cancer is more likely to develop in older people. More than 40 out of 100 bowel cancer cases in the UK each year are diagnosed in people aged 75 or over.⁴

The NHS bowel cancer screening programme is a home-testing kit that is sent to people aged 54 to 74, every 2 years, in order to help detect bowel cancer at an early stage, when it's easier to treat.

Bowel cancer rarely occurs before the age of 50, but specialists always have it in the back of their minds, particularly if it runs in the family. If several members of your family have suffered from it, then your risk of getting it is increased further.

Also, the younger a person is when they get bowel cancer, the more likely it is to have a genetic cause.

People with bowel conditions such as Crohn's disease and ulcerative colitis are also more likely than the general population to develop bowel cancer because the bowel lining is inflamed. The risk of developing bowel cancer increases with the length of time the patient has had the disease.

How can you help prevent bowel cancer?

Diet

Red meat — Although it is difficult to find a direct cause between diet and cancer, there are some foods that can affect the risk of bowel cancer. A diet containing a lot of red and processed meats (such as steak, smoked meat, ham, bacon, sausages and tinned meat) can increase the risk of developing cancer of the bowel.

It is estimated that around 13 out of 100 bowel cancer cases (around 13%) in the UK are linked to eating these meats.⁵

Fibre — A well-balanced diet, high in fibre, is a good idea as evidence suggests that too little fibre can increase the risk of bowel cancer, around 30% of cases are caused by too little fibre.⁵ Lots of fresh fruit, vegetables and unrefined grains, for example porridge, are good. Choosing brown rather than white bread is another good source of fibre.

>Explore our recipes that are full of fibre

Exercise

Try to maintain a healthy weight and be physically active, as obesity can increase your chance of bowel cancer. Cancer Research UK state: “There is strong evidence which shows that people who are more physically active have a lower risk of bowel cancer.”⁵

What is the bowel cancer screening process?

There are two main stages of testing for bowel cancer.

1) The home screening test

This test looks for hidden blood in samples of your poo. It is an easy test to do and can be done in the privacy of your own bathroom. You just need to collect a poo sample using your kit which will have instructions to follow. It is then sent off to a laboratory to be analysed.

You receive your results through the post usually within two weeks. If no blood is seen, you will be sent another kit in two years. Use the kit when you receive it, even if you have no signs of bowel cancer. The earlier a bowel cancer is detected, the easier it is to treat and the better the outcome.

If any blood is detected, you may have to repeat the test or be referred to see a specialist screening practitioner at a hospital where you may be offered a colonoscopy.

2) A colonoscopy or camera test

This involves passing a thin tube with a camera on the end up through the bottom to look along the colon and the inside of the bowel. You are given a sedative for the test, so you are sleepy but not knocked out. This investigation will be fully explained – including the necessary preparation – and you will have the opportunity to ask any questions.

A colonoscopy will only be performed if your doctor thinks it is needed.

How is bowel cancer treated?

There are many different types of treatment depending on the position of the tumour and how advanced it is (often referred to as ‘staging’).

In general, surgery, radiotherapy and chemotherapy can all be used.

Surgery — if the cancer is detected early, many people will undergo surgery to remove the tumour.

Radiotherapy — this uses radiation to kill cancer cells and may be used if the bowl cancer is in your rectum or the cancer has spread to other parts of the body.⁶

Chemotherapy — may be used after surgery just to make sure no cancerous cells are left behind. It may also be used in cases where cancer has spread to other parts of the body.

If the cancer has spread, your specialist will suggest further treatment. If it has moved to other vital organs, stage 4, you will be referred to a palliative care team to help prolong life and provide relief.

Bowel Cancer UK has more information on how bowel cancer is graded and the stages.

Side effects depend on the exact operation performed, which drugs are given and which treatment option is used. One area that cancer affects is diet and nutrition. Read more in our How does cancer affect diet and nutrition? article.

Receiving news that you’ve got cancer is hard to process and support will be given from doctors and nurses who will be there to help answer any questions. We've also got tips in our Talking about cancer hub that can help with having those difficult conversations with loved ones.

If you do receive a cancer diagnosis, the news can feel overwhelming and you’ll have a lot of questions. Explore our cancer care articles for more information. If you're a member with AXA Health, here's more information on dedicated cancer support you may have access to.

Useful resources

• Bowel Cancer UK
• Cancer Research UK
• Maggie’s

References

1. How common is bowel cancer? - Cancer Research UK
2. What Are The Stages Of Bowel Cancer? - Check4Cancer
3. Symptoms of bowel cancer - NHS
4. Risks and causes of bowel cancer – Cancer Research UK
5. Diet – Cancer Research UK
6. Main treatments for bowel cancer - NHS