Colonoscopy

People with Lynch syndrome are encouraged to have a colonoscopy (hover over: medical check on the inside of your bowel) every 2 years. This is because of the higher chance of developing bowel cancer.

Colonoscopies let the doctor see exactly how the inside of your bowel is. Some polyps (hover over: small growths on the lining of the bowel) may be removed immediately, which could stop them developing into bowel cancer. Doctors may also find early bowel cancer so it can be treated.

Some people want to know more about what to expect. This session will tell you about:

The colonoscopy
Bowel preparation
Further information

The colonoscopy

The doctor uses a flexible tube about as thick as a finger with a light at the end. The tube is carefully passed through the anus into the rectum and into the large bowel. They will usually give you gas and air to relax you and make the test more comfortable. You may also be offered painkillers or sedation (hover over: medicine given through a small tube in your arm to help you relax) to make you feel more comfortable.

The tube is connected to a television system where pictures can be seen.

If you would like to find out more, Bowel Cancer UK and the NHS website have very useful resources and videos.

Benefits of having a colonoscopy

If you have regular colonoscopies, your chance of dying from bowel cancer is more than halved.

Out of 100 people with Lynch syndrome, having regular colonoscopies prevents between 40 and 60 people from getting bowel cancer.

Having regular colonoscopies increases the chance of bowel cancer being found at an earlier stage, when it is more treatable. Doctors can remove any polyps found during colonoscopy, which reduces the chance of developing bowel cancer.

Side effects of having a colonoscopy

Colonoscopies are safe but common side effects are discomfort, bloating and pain.

Rarely, bleeding or perforation (hover over: a tear in the lining of the bowel) can occur. This happens for:

1 in 1500 colonoscopies when no polyps are removed
1 in 200 colonoscopies if polyps are removed

Side effects of gas and air (Entonox)

Gas and air can cause you to feel lightheaded, sick, sleepy or unable to concentrate

Side effects of being sedated for a colonoscopy

Sedation can make you feel drowsy for some time afterwards, your healthcare practitioner will be able to tell you more. Following a sedative, you should not drive home afterwards, drink alcohol for 24 hours or operate machinery for 24 hours. For more information, click here.

Before your colonoscopy you will be asked to avoid certain foods for a few days and then drink a strong laxative (hover over: a drink that will make you need to poo) to clean your bowel. This drink is generally referred to as bowel preparation or “bowel prep”. For some people this is the hardest part of having a colonoscopy.

The bowel prep is important to let the doctor see your bowel properly. If people do not follow the instructions to prepare their bowel, the colonoscopy might need to be repeated.

There are different types of bowel prep. A specialist nurse will tell you about your bowel prep and what foods to avoid.

How to cope with the Bowel Prep

There are some tips which have helped some Lynch syndrome UK

Mix Coke Zero/Diet coke with the bowel prep. You can read more about this here
Chill the bowel prep in the fridge before drinking
Drink the bowel prep through a straw so you don’t taste it as much?
Have something else to drink in between each swallow of the bowel prep
Follow a Low Residue diet for the two or three days before the bowel prep. The general recommendation is to follow this diet for 24 hours before the bowel prep, but it helps some people to follow the diet for longer. St Mark’s Hospital produced this diet guide to follow in the three days before your colonoscopy.

For further advice and support, please follow the following links:

Government Helping you decide leaflet
Bowel Cancer UK - Going for a colonoscopy
NHS - What is a colonoscopy?
An Easy Guide to having a Colonoscopy

We gratefully acknowledge the work of Laura Monje Garcia, The Royal Marsden NHS Foundation Trust, and St. Mark’s Hospital in helping us prepare this session.