NHS Bowel Scope Screening: Information for Primary Care

Bowel Scope Screening

Bowel scope screening is a new part of the NHS Bowel Cancer Screening Programme and is being rolled out across England from 2013. It involves once-only flexible sigmoidoscopy for all men and women around the time of the 55th birthday. They will all receive a leaflet called Bowel scope screening along with their appointment letter.

Bowel scope screening prevents colorectal cancer by detecting and removing adenomatous polyps in the rectum and sigmoid colon. People with high risk polyps are invited for subsequent colonoscopy.

Bowel scope screening does not usually require sedation. It requires an enema to be taken at home on the day of the procedure. The enema is sent to the person invited by the screening centre about 2 weeks before the appointment, along with instructions to take it an hour before leaving home.

Results of bowel scope screening are sent to the person and their GP.

If someone chooses not to have bowel scope screening when they are invited at age 55, they may ask for an appointment up until their 60th birthday by calling the Freephone helpline number 0800 707 60 60.

Whether or not they have had bowel scope screening, everyone will still be invited to take
part in Faecal Occult Blood testing every two years from the age of 60.

There will be no bowel scope screening catch-up for people currently aged 55 to 59.

Deciding not to have bowel scope screening may be a reasonable choice. Please reassure  patients that choosing not to have it will not affect their future health care.

What are the risks of bowel scope screening?

Minor rectal bleeding after the procedure may occur but about 1 in 3,000 have serious bleeding needing hospital admission.

There is a very small chance of bowel perforation (about 1 in 30,000).

What are the benefits of bowel scope screening?

The key benefit of bowel scope screening is prevention of colorectal cancer. Bowel scope
screening was found to reduce the incidence of colorectal cancer over 11 years’ follow up from 5 in 300 to 3 in 300 in a UK randomised controlled trial; in other words, 2 cases of colorectal cancer are prevented for every 300 people screened.

Bowel scope screening also reduces colorectal cancer mortality. It reduces colorectal cancer deaths over 11 years’ follow up from 2 in 300 to 1 in 3001; in other words, 1 colorectal cancer death is prevented for every 300 people screened.

What are the possible results and what happens if high risk polyps are found?

About 95% of people who have bowel scope screening once at age 55 to 64 receive a normal result (no polyps or very small polyps only).

About 1 person in every 300 (0.3%) will have colorectal cancer found during bowel scope

About 5% will be invited for follow-up colonoscopy because high risk polyps are found. These are defined as polyps that are large (>1 cm in diameter), have villous histology, show severe dysplasia, and or are multiple (3 or more). Before having a colonoscopy, people will be invited for an appointment with a Specialist Screening Practitioner (a specialist nurse) to discuss this and to receive instructions about preparing for it.

At colonoscopy, further polyps may be removed. Generally, people will subsequently be invited for surveillance colonoscopy either in 1 year’s time or 3 years’ time, depending on the number and size of the polyps. Of the people who attend colonoscopy, about 6% will have colorectal cancer found.

If very numerous or large polyps are found at bowel scope screening or colonoscopy, people may be referred directly for surgery. If someone is not suitable for colonoscopy, they will usually be offered CT colonography.

Other issues your patient may wish to discuss

What if the enema doesn’t cause a bowel movement before leaving for the screening

If the enema hasn’t caused a bowel movement within one hour, the person is unlikely to have one and should be able to travel.

Pain and embarrassment

Some people find bowel scope screening painful. About 80% of people said they felt no pain or only mild pain but about 3% people reported that it was severely painful.

About 5% of people report that bowel scope screening was embarrassing.

False negatives

False negative results may occur – bowel scope screening may not detect colorectal adenomatous polyps in about 20% of people who have them.

Colorectal cancer may develop after a normal result so it is important that people are
encouraged to present to their GP if they have had any of these symptoms for more than 3 weeks:

  • rectal bleeding
  • change of bowel habit
  • loose bowel motions
  • abdominal bloating or pain
  • abdominal lump
  • unexplained tiredness or weight loss

For more detailed information and further references please see:

Contraindications to bowel scope screening

  • Total colectomy or colostomy
  • Cardiac surgery in previous 3 months
  • Exercise tolerance of less than 100 yards due to dyspneoa
  • Active inflammatory bowel disease

Other special circumstances

Special arrangements may be needed for some patients, for example:

  • previous colorectal cancer
  • myocardial infarction in previous 6 months
  • renal dialysis
  • anticoagulant therapy

Your patient should telephone the NHS Bowel Cancer Screening Programme Freephone Helpline on 0800 707 60 60 for advice. Please refer to the clinical guidelines below, all available at www.bsg.org.uk/clinicalguidelines/endoscopy/index.html:

  • Consensus guidelines for the safe prescription and administration of oral bowel-cleansing agents 2012
  • Guidelines for colorectal cancer screening and surveillance in moderate and high risk groups 2010
  • Antibiotic prophylaxis in gastrointestinal endoscopy 2009
  • Guidelines for the management of anticoagulant and antiplatelet therapy in
    patients undergoing endoscopic procedures 2008
  • NICE Clinical Guideline: The diagnosis and management of colorectal cancer 2011


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