Tests and treatments
Polyp resection with snare
What is it?
Depending on the size, location and complexity of the polyp, the endoscopist may opt for a classic polyp resection with snare, for endoscopic submucosal dissection (ESD) or for piecemeal endoscopic mucosal resection (EMR).
The choice for ESD or EMR is always taken in consultation with your attending physician and after consideration of many factors.
Classic polyp resection with snare
This is the simplest way to remove a polyp. A metal snare is put around the polyp and tightened, cutting off the polyp. An electric current may or may not be used.
This technique is used to remove polyps of up to 2 cm. Larger polyps are removed using ESD or EMR.
Endoscopic submucosal dissection (ESD)
To remove larger polyps or cancer in an early stage, endoscopic submucosal dissection (ESD) may be chosen. This can be used for abnormalities in the oesophagus, stomach as well as intestines.
The technique was developed in the early 1990s in Japan. It consists of cutting the abnormality from the mucous membrane using a tiny electric knife, separating it from the underlying muscle layer. For this technique, fluid is injected in the space between the mucosa and the muscle layer to widen it. This ensures that the procedure can be done more safely and faster.
The important benefit of ESD is that the polyp can always be submitted to the anatomical pathologist in one piece. This allows for a very detailed diagnosis so that subsequently, correct follow-up can be offered to the patient.
At the same time, the risk of local recurrences is reduced, as the abnormality has been removed en bloc. This is especially important in case of suspected high-grade dysplasia or carcinoma. This way, surgery can be avoided for a significant percentage of patients.
Indications for ESD include polyps in the oesophagus, stomach or intestines from 20 mm which are suspected of turning malignant. This malignancy must be in a very early stage (maximum T1 tumour). An experienced endoscopist can estimate the stage based on the surface characteristics of the polyp.
Additionally, ESD can also be a safe option for resection of polyps with major submucosal fibrosis (scarring), for instance in the context of polyp recurrence after previous polypectomy or in the context of IBD.
Endoscopic mucosal resection (EMR)
Another option for the removal of large polyps is endoscopic mucosal resection (EMR). For this procedure too, fluid is injected in between the polyp and the underlying muscle layer to allow for the safe capture of the polyp with a snare. The polyp is cut through completely and, depending on the size, this can be done in pieces, a so-called ‘piecemeal EMR’. The final result is, of course, that no remaining polyp tissue can be seen.
The big advantage of this procedure is that the removal of the polyp is clearly faster than with ESD and carries less risk of complications. However, compared to ESD, the polyp will usually have to be analysed in the form of separate pieces, which may be more complicated for the pathologist. Additionally, the risk is higher that microscopically small pieces of the polyp remain in place which will grow back.
Preparation and course of the procedure
- As the resection can be done during a colonoscopy or gastroscopy, ask your physician for the specific guidelines on the preparations and on the medication you are allowed prior to the procedure.
- Please inform your physician if you are sensitive to latex or contrast agents.
- Leave removable dentures in your room. Damage to teeth (higher risk if teeth are in a poor condition) cannot be ruled out during an endoscopy or anaesthesia.
- Polyp resection through ESD or EMR is usually performed under anaesthesia that is administered by an anaesthetist;
- ESD and EMR standard include one overnight stay in hospital. Depending on the course of the procedure, the physician may decide to allow you to return home on the day.
Things to think about
Do not hesitate to ask for further explanation should you have any doubts or queries!
Make sure to let us know about:
- Allergy, sensitivity or intolerance (e.g. latex, Lidocaine, etcetera)
- Clotting problems or use of blood thinners (e.g. Marevan, Sintrom, Marcoumar, Ticlid, Plavix, Pradaxa, Xarelto, Aspirin, etcetera)
- Artificial valve or prosthetic: some patients require antibiotics before and after the procedure
- Epilepsy, diabetes, chronic heart, lung and kidney disorders: special attention to medication required
Safety and hygiene
We are an experienced and well-trained team, equipped with a modern infrastructure.
The anaesthetic is administered by an anaesthetist.
The procedure is performed in an endoscopy room that is fitted with all the necessary anaesthesia equipment and endoscopy instruments.
Before and after every examination, each endoscope is thoroughly cleaned and disinfected in an automatic cleaning and disinfection machine in a controlled procedure. Our disinfection protocols meet European standards. For the polyp resection, almost all materials used are disposable. Any reusable materials are cleaned and sterilised by the Central Sterilisation Department of the hospital.
Depending on the size of the polyp, the number of polyps that have been removed and any medication you might use, bleeding may occur after the procedure. This can happen up to ten days after the procedure. There is also a very small risk that a small hole is made in the intestine. This can usually be closed by way of endoscopy but sometimes this may require your stay in the hospital to be extended. Only in very rare cases is it necessary to take additional steps. Fortunately, these complications are rare. Contact your physician for a more detailed explanation.
After the procedure, you also may experience slight discomfort such as throat irritation, stomach discomfort, flatulence, bloated stomach, drowsiness and dizziness. This usually disappears by itself.
Sometimes, phlebitis can develop at the IV insertion site (painful swelling). If required, you will be given an ointment for this.
Contact us if you have the following symptoms after the procedure:
- Persistent severe pain
- Blood loss (red or black stools)
- Any concerning symptom
Centres and specialist areas
Latest publication date: 05/02/2021
Supervising author: Dr Vanderstraeten Erik