What are the symptoms?

Common signs and symptoms of bowel cancer may include:

• A change in bowel habits.
• Diarrhoea, constipation, or feeling that your bowel doesn't empty completely.
• Blood in your bowel motion.
• Bowel motions that are narrower than usual.
• General abdominal discomfort (frequent gas pains, bloating or cramps).
• Unexplained weight loss.
• Tiredness.

As these symptoms are often caused by other conditions it is important to check with a doctor.

How is bowel cancer diagnosed?

A number of tests can be performed to diagnose bowel cancer.
You may have some or all of the following tests:

Rectal and abdominal examination

During this examination the doctor inserts a gloved finger into the rectum to find any lumps, blood or swelling. The doctor will also gently feel the surface of the abdomen to check for anything abnormal.

Blood count

A blood count is made to check the number of red cells in your blood and to see how well your kidneys and liver are working.

A test for blood in the bowel motions

A small sample of bowel motion is put on a filter paper and tested for the presence of blood.

Sigmoidoscopy

The doctor inspects the rectum and lower part of the bowel using a short, straight tube called a sigmoidoscope. The doctor may also take a small sample of cells, known as a biopsy. This sample is then examined under a microscope.

Barium enema

A radiologist puts a mixture containing barium into the rectum, and then takes x-rays. The barium shows up on the x-rays and gives a clear picture of the bowel. After the test, the mixture is passed out in the bowel motions.

Colonoscopy

A specialist inspects the entire length of the large bowel by gently inserting a long, flexible tube called a colonoscope into your rectum and then into your colon. A sedative is given before the colonoscopy. The specialist may take a biopsy, which is examined under a microscope.

Occasionally a colonoscopy is used to remove a very small cancer that is in a polyp. When these tests have been completed more investigations will be needed to see if the cancer has spread.

You may have the following tests before or after surgery:

• chest x-ray - to check the cancer hasn't spread into your chest.
• CT scans and ultrasound tests of parts of your body, such as liver, chest and abdomen.

Ask the medical staff if it is appropriate for your partner or friend to stay with you when the tests are carried out.

Related topics

How is bowel cancer treated? See Bowel cancer treatment

What is bowel cancer? See Bowel cancer

How does cancer form? For more information on cancer, see What is cancer?, What causes cancer?

What does that term mean? See Cancer glossary

Original material provided by the Cancer Society, 2002. Reviewed by everybody, January 2005.