What is a blocked bowel (bowel obstruction)?

Sometimes, colon cancer can narrow the bowel, which stops poo (stools) from passing through. This is called a bowel obstruction. It is sometimes called an intestinal obstruction.

Symptoms of a bowel obstruction

A bowel obstruction can cause symptoms such as abdominal (tummy) pain, bloating and vomiting. It usually needs to be treated urgently. A blocked bowel can be relieved in different ways.

Stenting to relieve a bowel obstruction

The doctor uses a colonoscope to insert an expandable metal tube (stent) into the blockage. They may also use an x-ray to see where to insert the tube. The tube then expands to hold the bowel open, so stools can pass through it again. You are usually given sedation to have this done.

You may have a stent for a short time before having an operation to remove the cancer. Or sometimes a stent stays in permanently to treat the blockage. Your doctors will explain what the aim of the stent is in your situation.

A part of the bowel with a stent inside

Surgery to relieve a bowel obstruction

Sometimes a bowel obstruction is treated with an operation to remove the blocked section of bowel. Most people have a temporary or permanent stoma after this operation. The surgeon may remove the cancer at the same time, or later in another operation.

If it is not possible to remove the cancer, the blocked bowel can be relieved by creating a stoma. This means you pass stools (poo) out of the stoma.

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    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

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