Gastroenterology - A guide to having an Endoscopic Mucosal Resection (EMR)

Introduction

This information leaflet gives details about a procedure called Endoscopic Mucosal Resection (EMR). This is a technique used to remove large polyps. We hope the information provided will answer all the questions you have but if anything is not clear or you have further concerns, please contact one of the numbers at the back of the leaflet.

What is a polyp?

A polyp is a growth that forms on the lining of the bowel. If left to grow, some polyps can turn cancerous. By removing polyps, your risk of developing bowel cancer is greatly reduced.

Why have I been referred for EMR?

We have found a large polyp in your bowel. Most polyps are very easy to remove, but in your case the polyp seen will require a more specialist technique called EMR to remove it.

Before your procedure

You will require further bowel preparation to clear the bowel out. Please take time to read the enclosed bowel preparation leaflet well in advance and follow the instructions carefully. If the bowel has not been cleaned out enough, it may not be possible to do the EMR.

During your procedure

From your point of view, the procedure may seem no different from your previous colonoscopy or sigmoidoscopy. The EMR often takes longer than a standard colonoscopy. How long it takes will depend on the size and position of the polyp. It can vary from ten minutes to over an hour. A sedative injection will be offered to help you relax during the test or you may have Entonox (“Gas and Air”) if this is appropriate. Most patients find EMR comfortable, however with longer procedures the gas used to inflate the bowel can become trapped and cause discomfort. If you do have discomfort it is important that you tell the Endoscopist so that if possible more sedation or painkiller could be given if appropriate or the test can be stopped.

The endoscopist will first:

• Use the endoscope (camera) to find the polyp in your bowel
• Confirm whether EMR is the best way to remove the polyp
• If so, it will then be removed using the endoscope equipment
• You may be asked to lie on your back, or on your side to give the Endoscopist the best view
• A cold pad will be placed on your leg or arm to connect you to the electrical Diathermy Equipment which is used to pass a small electrical current through the polyp to help remove it
• Liquid will then be injected into the bowel wall underneath the polyp, to raise it up on a cushion of fluid. You will not feel this injection at all. The liquid is often coloured blue so that the Endoscopist can see where it has gone
• A wire loop will then be placed over the polyp and a small electrical current used to cut through the polyp tissue. Again, you should not feel this happening. If you do feel discomfort during this process please tell the Endoscopist
• The polyp may be removed in one piece, but bigger polyps are more commonly taken off in small pieces. This process can take some time
• There should be very little bleeding. Any areas of bleeding can be treated by placing special metal clips through the endoscope. These will drop off after a few days and pass unnoticed when you go to the toilet
• Sometimes the Endoscopist will complete the EMR by burning away tiny pieces of remaining polyp using a treatment known as argon plasma coagulation (APC). This is a safe way to deliver heat (cautery) to treat small blood vessels to stop bleeding or to destroy small areas of polyp tissue left behind following removal of larger polyps. During the use of APC gas enters the bowel which may become uncomfortable like ‘trapped wind pain’ – do tell the Endoscopist if the ‘wind pain’ becomes severe
• When the EMR is complete, the pieces of polyp tissue will be sent to the laboratory for further testing, this will help the Endoscopist to decide what further treatment you may require. These results can take up to 2 weeks.

After your procedure

You will be able to rest in the recovery area until the immediate effects of any sedation given have worn off and you have recovered from the procedure. Most patients can go home the same day. If sedation has been given we would insist that you are accompanied home and have a responsible adult at home with you for that day, and overnight. Following sedation you are also unable to drive for 24 hrs.

Sometimes (for example if the polyp was very large, or you experience a lot of pain) the Endoscopist might advise you to stay in hospital overnight as a precaution.

In general, a further colonoscopy or sigmoidoscopy will be required between 2-6 months after the EMR, to check the entire polyp has gone and the scar has healed. This is usually a quick procedure. Occasionally, more treatment is required.
 
Once the Endoscopist is sure the polyp has completely gone, a further colonoscopy will usually be arranged at an appropriate interval

What are the risks of EMR?

EMR carries a higher risk than ordinary colonoscopy and polyp removal. This is because it is used to remove much larger polyps. It is still by far the safest way to remove large polyps and is much less risky than surgery, which is the only other way of removing large polyps.

The main risks are perforation, bleeding and pain.

• Perforation means making a hole in the bowel wall. This is a serious problem and, if it happens, you will always require a stay in hospital. Occasionally perforations heal with antibiotics and sometimes they can be treated with the endoscope but occasionally an emergency operation is required. As with any bowel operation, a stoma (bag on your abdomen) is sometimes required, although this would usually be temporary.

Perforation happens, on average, once in every 200 EMR procedures, however the risk is higher with larger polyps. This will be discussed with you when your consent is taken. A perforation may happen at the time of the procedure or (more rarely) up to two weeks later. You will be given an information sheet after the procedure to let you know what to look out for.

• Severe bleeding from the back passage happens, on average, once in every 50 EMR procedures. The risk will depend on how big the polyp is, and where in the bowel it is found. Sometimes the bleeding will happen immediately after the test but it can also occur up to 14 days later. If bleeding does occur, it often stops on its own but occasionally a blood transfusion or further endoscopies are needed. Very rarely an X-ray procedure or an emergency operation may be necessary to stop it.
• Some abdominal discomfort is expected for a day or two after the procedure. This is because the bowel wall is starting to heal itself. In about one case in every 20, the pain may be more severe and last longer. In some cases it will be necessary to spend a day or two in hospital so that strong pain killers can be given. If you have pain at home after the EMR, you can take paracetamol or codeine-containing pain killers. Aspirin and ibuprofen (Nurofen) should be avoided because they can increase the risk of bleeding.

Travelling abroad following EMR?

There is a small risk of side-effects or problems happening for up to 14 days after an EMR. For this reason, you are strongly advised to avoid air travel for 2 weeks.

Is EMR always successful?

Large polyps are removed by EMR to stop them turning cancerous. Sometimes when the Endoscopist sees the polyp, he/she can tell that it has already started to turn cancerous. In this situation, a surgical operation may be recommended because it is important to completely remove all the cancerous cells.

Sometimes the polyp is found to be too big or technically difficult to remove by EMR. In this situation, surgery may be recommended, or you may be referred to an Endoscopist at another hospital who specialises in difficult polyps.

Occasionally, the polyp is successfully removed by EMR but the pieces sent to the laboratory show that it contains cancerous cells. In this situation, once again, surgery is usually necessary.

If surgery is recommended, this will be planned at a later date and you will have plenty of time to discuss this with a doctor in clinic.

Are there any other ways of dealing with my polyp?

Yes. There are two other options:

Do nothing and leave the polyp where it is. This is usually not a good idea because large polyps often turn cancerous if they are left to grow.

Remove the polyp by having a surgical operation on the bowel. Although usually a straightforward procedure, surgery always carries a risk of serious complications. Part of the bowel will usually be removed and this may sometimes cause long-term side effects. Even if the operation is done by key-hole surgery, you will still be in hospital for a few days. Rarely surgery can result in a stoma (bag on your abdomen), although this may only be temporary.

More Information

If you wish to discuss the EMR procedure or have any further questions, please contact the number below.

Endoscopy Patients Contact
The Endoscopy Unit 0161 206 5959