Bowel cancer

Cancer occurs when body cells alter, multiply and interfere with ‘normal’ cells.

Bowel cancer is also called colorectal cancer and includes large bowel cancer (colon cancer) and cancer of the back passage (rectal cancer or cancer of the rectum).

Bowel cancer – symptoms

The most common symptoms of bowel cancer include;

  • a lasting change in bowel habits, for example; the number of times you go to the toilet, the consistency of your faeces (stool);
  • bleeding from your rectum which can show up in your faeces
  • a lump in the right side of your abdomen or in your rectum
  • Losing Weight
  • Pain in your abdomen or rectum

Cancer of the bowel may cause a blockage (bowel obstruction). The symptoms of this are gripping pains in the abdomen, feeling bloated, constipation, and being sick.

These symptoms may be caused by another problem but symptoms should be discussed and checked by your GP.

Causes of bowel cancer

  • The biggest single risk factor is age.
  • Bowel cancer can also be genetic – you are more at risk of developing bowel cancer if an immediate relative had bowel cancer.
  • A high-fat diet, lack of exercise, high alcohol intake or smoking can also contribute to risk.
  • If you have had inflammatory bowel disease e.g. Crohn’s or Ulcerative Colitis, you may also have a higher risk of getting bowel cancer.

Diagnosing bowel cancer

There are a number of tests that can be carried out to see if you have bowel cancer. These include:

A digital rectal examination (DRE) – Your GP gently placing their finger into your anus, and then up into your rectum. A DRE is a useful way of checking whether there is a noticeable lump inside your rectum. This is found in an estimated 40-80% of cases of rectal cancer. A DRE is not painful, but some people may find it a little embarrassing.

If your symptoms suggest that you may have bowel cancer, or the diagnosis is uncertain, you will be referred to your local hospital for further examination.

Two tests are commonly used to confirm a diagnosis of bowel cancer:

Sigmoidoscopy – this procedure will probably be delivered by a specialist that your GP has sent you to. This procedure uses a long tube approx. 10 inches long which is inserted into the anus. This helps the doctor see the whole of the rectum. This is a quick procedure. The doctor will pump air into the bowel and may decide to take a small piece of tissue from the rectum for examination. This is done with forceps and is not painful.

Colonoscopy – this test uses a long scope which can provide a picture of the whole colon, sometimes using a small camera to send pictures to a monitor. The bowel needs to be prepared to make sure it is completely clear. You may be given a special diet to eat for a few days before the examination and a laxative on the morning of the examination. You will be given a sedative to help you relax, after which the doctor will insert the colonoscope into your rectum and move it along the length of your large bowel. As with a sigmoidoscope, the colonoscope can be used to obtain a biopsy, as well as relaying images of any abnormal areas.


Surgery is often but not always necessary to remove the cancer.

When deciding what treatment is best for you, your doctors will consider:

  • The type and size of the cancer.
  • Your general health.
  • Whether the cancer has spread to other parts of your body.
  • What grade it is.

There are several treatments for bowel cancer, including:

  • surgery
  • chemotherapy
  • radiotherapy
  • biological therapy

Surgery – Colon Cancer

If the cancer is at a very early stage, it may be possible to remove just a small piece of the lining of the colon wall. This is known as local excision.

If the cancer has begun to spread into the muscles surrounding the colon, it will usually be necessary to remove an entire section of your colon. Removing some of the colon is known as a colectomy.

Depending on the location of the cancer, possible surgical procedures include:

  • left-hemi colectomy, where the left half of your colon is removed
  • transverse colectomy, where the middle section of your colon is removed
  • right-hemi colectomy, where the right half of your colon is removed
  • sigmoid colectomy, where the lower section of your colon is removed

There are two ways that a colectomy can be performed:

  • In an open colectomy, the surgeon makes a large incision in your abdomen and removes a section of your colon.
  • A laparoscopic colectomy is a type of ‘keyhole surgery’, where the surgeon makes a number of small incisions in your abdomen and uses special instruments guided by a camera to remove a section of colon.
  • Both techniques are thought to be equally effective in removing cancer and have similar risks of complications. Laparoscopic colectomies have the advantage of a faster recovery time and less post-operative pain.

Laparoscopic colectomies should now be available in all hospitals carrying out bowel cancer surgery, although not all surgeons perform this type of surgery. If you are considering having your bowel cancer surgery done using keyhole surgery, discuss this with your surgeon.

During surgery, nearby lymph nodes may also be removed. It is usual to join the ends of the bowel together after bowel cancer surgery, but very occasionally this is not possible and a stoma is needed.

Surgery – Rectal Cancer

Two common surgical procedures can be used to treat rectal cancers:

  • Low anterior resection – Low anterior resection is a procedure that is used to treat cases where the cancer is in the upper section of your rectum. The surgeon will make an incision in your abdomen and remove the upper section of your rectum, as well as some surrounding tissue to make sure that any lymph glands containing cancer cells are also removed. They will then attach your colon to the lowest part of your rectum or upper part of the anal canal. Sometimes, they turn the end of the colon into an internal pouch to replace the rectum. You will probably require a temporary stoma to give the join-up time to heal.
  • Abdominoperineal resection – Abdominoperineal resection is used to treat cases where the cancer is in the lowest section of your rectum. In this case, it will be necessary to remove a large section of your rectum and surrounding muscles to reduce the risk of the cancer regrowing in the same area. This involves removing the anus and its sphincter muscles too, so there is no option except to have a permanent stoma after the operation. Bowel cancer surgeons always do their best to avoid giving people permanent stomas wherever possible

Chemotherapy and radiotherapy can be used to prevent the cancer from spreading further along the bowel or to other organs.

Further Information

For further and more detailed information about Bowel cancer please contact Cancer Research UK – the UK’s leading charity dedicated to cancer research Tel: 0808 800 4040

You can also contact Lyn’s Bowel Cancer Campaign. Lyn’s Bowel Cancer Campaign is a charity that raises awareness of bowel cancer and provides information and advice. Call them for symptoms information on their 24 hour hotline 0870 2424 870 or call them on 020 8891 5937 or alternatively, visit their website

You can also obtain a bowel cancer screening from the NHS. The NHS Bowel Cancer Screening Programme offers screening every 2 years to all men and women aged 60 – 69. People in this age group will automatically be sent an invitation, then their screening kit so they can do the test at home.

Your GP will provide your contact details, so it is important that he or she has your correct name and address. After your first screening test, you will be sent another invitation and screening kit every 2 years until you reach 69. If you are 70 or over, you can ask for a screening kit. You can contact your programme hub on Freephone 0800 707 60 60.

If you have experienced any of the symptoms described above, please see your GP or healthcare professional. These symptoms could be caused by another problem, not necessarily bowel cancer.

Help for incontinence problems

If you are concerned about any incontinence or bladder problems and it is starting to affect your day to day life make an appointment to see your doctor, continence nurse or specialist physiotherapist. A continence nurse and specialist physiotherapist are healthcare professionals who specialise in bladder and bowel problems.