Symptoms and diagnosis of bowel cancer

Symptoms of bowel cancer

The symptoms of bowel cancer can include:

  • A change in your normal bowel motion, such as diarrhoea or constipation.
  • Feeling you have not emptied your bowel fully after a motion.
  • Pain or discomfort in your abdomen (tummy) or back passage.
  • Trapped wind or fullness in your tummy.
  • Weight loss.
  • Tired and breathless (due to anaemia from blood loss).
  • Rectal bleeding or blood in stools.

These symptoms can also be due to complaints other than bowel cancer. But do get them checked out by your doctor, especially if they go on for more than 4 to 6 weeks.

For more information read our cancer prevention leaflet Bowel cancer – What you should know.

Diagnosis of bowel cancer

If you are worried about any symptoms of bowel cancer, visit your G.P. He or She can do a small number of tests first, such as;

  • Rectal exam
  • Blood tests to check for anaemia
  • Stool sample to check for hidden blood

Rectal exam

  • In this test your doctor puts a gloved finger into your back passage to feel for lumps or swelling. This quick test may be slightly uncomfortable but does not hurt.

Special tests

If your GP feels more tests are needed, they might refer you to hospital to have some of these tests.

  • Proctoscopy
  • Sigmoidoscopy
  • Colonoscopy
  • CT colonography

Proctoscopy: In this test your doctor looks inside your back passage. To do this, he or she passes a short thin tube into your back passage while you are lying on your side. Air is then pumped in so that the doctor can see the area more clearly.

Sigmoidoscopy: A longer tube with a camera is used in this test. The tube is carefully put into your back passage. A light inside the tube helps the doctor see clearly. Your doctor can see any abnormal areas in one part of your bowel. He or she can take samples of the cells in your bowel. This is called a biopsy.

Colonoscopy: This test is like a sigmoidoscopy, except your whole bowel can be looked at. Photos and samples of your bowel can be taken during this test. This test can take about an hour and can be uncomfortable. You may be given sedation , just before the test ,to help you relax.

CT colonography: This is a newer test and not available in all hospitals. It is also known as a virtual colonoscopy. Air is put into your bowel by a tube put into your back passage. A number of CT scans are taken to look at your bowel. A biopsy cannot be taken during this test.

Other tests

  • CT scan
  • MRI scan
  • Ultrasound scan
  • PET scan

These scans can help to stage the cancer.

Learn more about the above tests

Staging of bowel cancer

The stage of cancer describes the size of your cancer and whether it has spread from its original area to other areas in the body. Knowing the stage of your cancer will help your doctor to decide on the best treatment for your cancer.

Your doctor will stage your bowel cancer using the TNM staging system. TNM refers to the size of the tumour (T), if it has spread to your lymph nodes (N), and if it has spread to other parts of your body as metastases (M). It is a complex system but it can be roughly described as the following:

  • Stage 1: The cancer is in the inner wall of your colon or rectum only.
  • Stage 2: The cancer is in the muscle layer of your colon or rectum and may have spread to nearby tissues.
  • Stage 3: The cancer has spread to nearby lymph nodes.
  • Stage 4: The cancer has spread to other parts of your body, for example your liver or lungs. This can also be called advanced cancer.

Bowel cancer screening

Testing for bowel cancer when you have no symptoms is called screening. Bowelscreen is the national bowel screening programme, funded by the government. The programme will offer a BowelScreen home test kit to women and men aged 60 to 69 every two years. Over time,  the programme will be expanded until the full 55 to 74 age group is reached.

For more information on bowel screening, vist the Bowelscreen website.

Continue to Treatment of bowel cancer

Date Last Revised: 
Friday, March 20, 2015