Cookies on the Bupa website

We use cookies to help us understand ease of use and relevance of content. This ensures that we can give you the best experience on our website. If you continue, we'll assume that you are happy to receive cookies for this purpose. Find out more about cookies


Bowel cancer

Key points

  • Bowel cancer is the third most common cancer in the UK.
  • You can get bowel cancer at any age but most people who get it are over 60.
  • Symptoms of bowel cancer include blood in your faeces.
  • Surgery is the most common treatment for bowel cancer.

Bowel cancer is a lump created by an abnormal and uncontrolled growth of cells that starts in your bowel.

How cancer develops

A Flash plug-in is required to view this animation.

About bowel cancer

Your large bowel (also called your colon) is the last section of your digestive system. Food passes through your small bowel (the longer, thinner part of your bowel) where nutrients are absorbed. Food waste then travels through your large bowel, where it becomes more solid faeces.

Your large bowel is divided into several sections including the ascending, transverse and descending colon. Your rectum (back passage), at the end of your large bowel, is where faeces collect before passing through your anus as a bowel movement.

Illustration showing the location of the large and small bowel

Bowel cancer, also known as colorectal cancer, is the third most common cancer in the UK; nearly 43,000 people were diagnosed with it in 2011. Bowel cancer is the name for any cancer of your large bowel, rectum and appendix. It also includes cancer in your small bowel but this is rare – only about 1,200 people get this type each year in the UK.

Usually, large bowel cancers develop from small, non-cancerous (benign) growths of tissue called polyps that can develop in your bowel or rectum. Sometimes polyps can become cancerous (malignant) over time.

The earlier bowel cancer is diagnosed, the better your chance of a cure. If you don't get treatment for cancer, it can grow through the wall of your bowel and spread to other parts of your body.

You can get bowel cancer at any age but you’re more likely to get it if you’re over 50.

Symptoms of bowel cancer

The symptoms of bowel cancer include the following.

  • Blood in your faeces. This may be mixed into your faeces or flecks on the surface, or you may see it in the toilet or on toilet paper. It’s a good idea to get into the habit of checking in the toilet before you flush.
  • Persistent changes in your bowel habit that last for longer than several weeks. This could be going to the toilet more often or having diarrhoea.
  • Weight loss without any obvious reason and/or losing your appetite.
  • Tiredness or breathlessness for no apparent reason. This may be caused by the small amount of blood loss from your bowel, which can result in anaemia. Anaemia is when there are too few red blood cells or not enough haemoglobin in your blood.
  • Pain, or a lump or swelling in your abdomen (tummy).

If you have any of these symptoms, see your GP.

Causes of bowel cancer

The exact reasons why you may develop bowel cancer aren't fully understood at present. However, your risk of bowel cancer is higher if you:

  • have a family history of bowel cancer
  • have an inherited bowel condition, such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome
  • have a long-term bowel condition, such as Crohn's disease or ulcerative colitis
  • have a diet that is low in fibre, fruit and vegetables and high in red and processed meats
  • have an inactive lifestyle
  • are obese
  • have type 2 diabetes
  • smoke
  • drink excessive amounts of alcohol

You’re also more likely to get bowel cancer as you get older.

Diagnosis of bowel cancer

Your GP will ask about your symptoms and examine you. He or she may also ask you about your medical history.

Your GP may examine your rectum. He or she will insert a finger (wearing a glove) into your rectum to feel for any lumps or swellings.

Your GP may refer you to a doctor or surgeon who specialises in colorectal disease.

Tests for bowel cancer include the following.

  • A colonoscopy is a test that will allow a doctor to look inside your large bowel. He or she will use a narrow, flexible, tube-like telescopic camera called a colonoscope.
  • A sigmoidoscopy is a procedure to look inside your rectum and the lower part of your bowel.
  • A barium enema involves placing a fluid containing barium (a substance which shows up on X-rays) into your bowel via your rectum. X-ray images of your abdomen then show the inside of your bowel more clearly.
  • A virtual colonoscopy uses a CT scan to create a three-dimensional image of the inside of your bowel.

If your doctor diagnoses bowel cancer, you may need further tests to find the size and position of the cancer.

These tests may include:

  • an ultrasound scan of your abdomen to see if the cancer has spread to your liver
  • a CT scan to show where the cancer is and whether it has spread
  • an MRI scan to give detailed pictures of your rectum if the cancer is lower down your bowel
  • a chest X-ray to check the health of your heart and lungs
  • blood tests to assess your general health

Screening for bowel cancer

Screening is important as it may detect bowel cancer in its early stages. There is a bowel cancer screening programme in England. If you're between 60 and 69, you will be sent a bowel cancer screening kit. In most areas, this has been extended to people aged between 70 and 75 but you can also request a kit if you're over 69. There are different programmes running in the rest of the UK. Ask your GP for information about the screening programme in your area.

The screening kit contains a faecal occult blood (FOB) test that can detect small amounts of blood in your faeces. The FOB test doesn't diagnose bowel cancer, but the results show if you need to have your bowel examined. However, even if you have a screening test with a normal result, if you have symptoms, it's important to see your doctor.

The Department of Health is also running a pilot screening programme in some parts of England. If you live in one of these areas, you will be invited to have a sigmoidoscopy test around your 55th birthday. You will still be sent a bowel cancer screening kit after you're 60.

Screening for people at a risk of bowel cancer

If you're more at risk of developing bowel cancer than the general population, you may have regular tests to check for bowel cancer. For example, this may be because you have a close relative who has had bowel cancer or a health condition puts you at risk.

Ask your GP for advice and see our frequently asked questions for more information.

Treatment of bowel cancer

The type of treatment you have will depend on the size of your cancer, its position and whether it has spread.


Surgery is the most common treatment for bowel cancer. You can have open surgery, in which your surgeon will make one large cut in your abdomen. Alternatively, you may be able to have keyhole surgery.

If you have cancer in your bowel, your surgeon will remove the part that is affected and join the two open ends together. He or she may also remove your lymph nodes. These are glands found throughout your body that are part of your immune system. They are often the first place the cancer spreads to.

It's possible your surgeon may not be able to immediately join the two ends of your bowel. He or she will then bring the end of your bowel out to the surface of your abdomen and create a stoma through your skin. If it's your large bowel, this is called a colostomy and if it's your small bowel, it's called an ileostomy. See our frequently asked questions for more information.

If you have cancer in your rectum, your surgeon will remove the cancer and the surrounding tissue. He or she may also remove your lymph nodes. Depending on how much of your rectum your surgeon needs to remove, you may need to have a colostomy.

A colostomy or ileostomy can be temporary, or it may need to be permanent. This will depend on your operation – ask your surgeon for more information.

Non-surgical treatments

Chemotherapy and radiotherapy

Sometimes it's not possible to remove all the cancer by surgery, so you may need to have treatment with chemotherapy and/or radiotherapy too. Chemotherapy uses medicines to destroy cancer cells and radiotherapy uses radiation.

Chemotherapy and radiotherapy aim to destroy any remaining cancer cells and prevent the cancer spreading further. They are sometimes used to shrink the tumour before or after surgery. They can also kill any cancer cells that might be left after surgery or help to reduce your symptoms.

Monoclonal antibodies

Monoclonal antibodies are medicines designed to recognise specific proteins on cancer cells. Monoclonal antibodies used to treat bowel cancer include:

  • bevacizumab
  • cetuximab
  • panitumumab

These medicines seek out cancer cells and stop them growing. They are sometimes used alongside chemotherapy. They can be used for various stages of cancer – ask your doctor for more advice.

Prevention of bowel cancer

If you take the following steps, it may help to reduce your risk of getting bowel cancer.

• Try to do 150 minutes of moderate exercise over a week in bouts of 10 minutes or more. You can do this by carrying out 30 minutes on at least five days each week. Alternatively, do 75 minutes of vigorous intensity activity twice a week.
• If you smoke, stop.
• Maintain a healthy weight.
• Eat five or more portions of fruit and vegetables every day.
• Cut down on the amount of processed and red meat you eat.
• Eat foods high in fibre such as wholegrain bread, cereals and pasta.
• Drink alcohol in moderation – no more than two to three units a day for women and three to four units a day for men.

Produced by Rachael Mayfield-Blake, Bupa Health Information Team, January 2014.

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.

Share with others

  • This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.

    Approved by Plain English Campaign The Information Standard memberHON Code


Living with and beyond cancer eBook and app

Helping others understand the physical, emotional, social and financial challenges faced by people after cancer treatment.

Download here

Worried about bowel cancer?

Bupa can help you detect early signs of bowel cancer with our Colon Health Check.

Interested in having chemotherapy at home?

With Bupa Home Healthcare you could choose to have your chemotherapy at home. For more info call 01279 456 789.