Bowel scope screening

The bowel scope screening test looks at the lower part of the large bowel. It can help detect polyps or cancers at an early stage.

What is bowel scope screening?

Bowel scope screening is a test that looks at:

  • the inside of the back passage (rectum)
  • the part of the large bowel closest to the rectum (the sigmoid colon).

This is where most bowel polyps and bowel cancers develop. Bowel scope screening only looks at the lower part of the bowel. It does not replace the FOB or FIT home screening test.

You have bowel scope screening as an outpatient at the hospital.

Before bowel scope screening

If you choose to have bowel scope screening, you will be sent an enema and instructions for how to use it. An enema is a liquid used to soften the poo. It does not give you diarrhoea, but you will need to go to the toilet straight away. This clears poo out of the lower part of the bowel and makes it easier for the nurse or doctor to see inside the bowel.

You use the enema on the day of the test. Most people find it easy to use.

What does bowel scope screening involve?

Bowel scope screening is done using a bendy tube with a light and camera on the end. This is called a sigmoidoscope. You lie on your left side and a doctor or nurse passes the tube into the back passage (rectum). A small amount of air is pumped into the bowel to make it easier to see inside. This can make you feel bloated for a few hours afterwards.

Bowel scope 

Most people find the bowel scope screening painless or have only mild discomfort. If you find it very painful, tell the doctor or nurse straight away. If you have pain, they will give you a gas that can relieve pain (Entonox®). This is sometimes called gas and air. You breathe it in through a mouthpiece.

During the test, the doctor or nurse will remove any polyps they find. They can also take samples of tissue (biopsies) from any areas of the bowel that look abnormal.

You can go home after the test is finished.

Getting your results

If your test result is normal, the doctor or nurse will tell you straight away. If the doctor or nurse removes polyps or takes biopsies during the test, you will get the results by post within 3 weeks.

Normal results

About 95 out of 100 people (95%) have a normal result from the test. This means the test found no polyps and nothing else abnormal in the bowel. If your test result is normal, the doctor or nurse will tell you straight away.

It is important to be aware of bowel cancer symptoms in future, even if you have a normal result.


Around 5 out of 100 people screened (about 5%) have polyps. The nurse or doctor usually removes any polyps they find. They will tell you if they have done this.

They send the polyp to the laboratory to be checked by a pathologist. This is a doctor who specialises in in studying tissue samples and cells.

Most polyps are not cancerous (benign).

If you had polyps removed during your bowel scope test, you will get the results by post within 3 weeks. This is to tell you whether you need a follow-up appointment or further tests. You may be offered another test to check all of your large bowel. This is usually a colonoscopy.

Your GP will also get a letter with your results.


Rarely, the screening will find bowel cancer. About 1 in 300 people who have bowel scope screening have cancer.

If cancer is found, it is likely to be at an early stage. Around 9 out of 10 of bowel cancers (about 90%) can be cured if found at an early stage.

Your nurse or doctor will arrange for you to see a specialist as soon as possible.

Risks of bowel scope screening

Bowel scope screening is a safe test. Most people do not have any problems after it. But rarely, there can be problems.

About 1 in 250 people have heavy bleeding after having a polyp removed. They may need to go into hospital to have this treated.

Sometimes the bowel can be torn or damaged, but this is very rare. If it happens, you will need an operation to repair the tear. Symptoms of a tear include:

  • severe tummy pain
  • a high temperature
  • bleeding from the back passage
  • being sick.

If you have any of these symptoms, contact your GP or go to your nearest emergency department A&E straight away.