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Results
You will usually be told straight after the procedure what was removed. Laboratory results generally take about one to two weeks and tell whether the polyp was an adenoma or contained cancer cells, and whether the removal was complete. They guide how soon you need your next scope and whether any further treatment is needed.
This article is educational and does not replace your doctor's advice. Seek urgent care for any red-flag symptoms.
What is it?
A polyp is a small growth on the inside lining of the gut, most often in the colon or stomach. Many are harmless, but some types (adenomas) can slowly turn into cancer over years, so removing them is a way to prevent cancer. Using the endoscope, the doctor can remove polyps with several techniques: polypectomy (snaring or cutting off small and medium polyps with a wire loop), endoscopic mucosal resection (EMR, where fluid is injected under a flat or larger polyp to lift it before it is removed, often in pieces), and endoscopic submucosal dissection (ESD, a specialised technique where a polyp or early lesion is carefully cut out in one piece through a layer deeper in the wall). Removed tissue is sent to the laboratory.
Why is it done?
Polyps are removed to prevent them from growing, bleeding or becoming cancer, and to check under the microscope what they are. For some early cancers or large flat lesions, endoscopic removal can be curative and may avoid surgery, if the laboratory results show it is suitable.
Who needs it?
- People in whom polyps are found during colonoscopy or gastroscopy
- People with larger or flat polyps that need EMR
- Selected people with early lesions or very large polyps who may be offered ESD at a specialised centre
- People with a family history or a past of polyps who need follow-up checks
Before the procedure
- Follow your unit’s bowel preparation instructions carefully if the polyp is in the colon; a clean bowel allows safe removal.
- Tell the team about ALL blood thinners (warfarin, apixaban, rivaroxaban, dabigatran, clopidogrel, aspirin) and diabetes medicines. Polyp removal carries a bleeding risk, so you may need a plan to pause medicines; never stop them yourself.
- Tell the team about allergies, heart or lung disease, pregnancy, and previous reactions to sedation.
- Arrange for an adult to take you home and stay with you, as sedation is usually used.
- Larger lesions (EMR or ESD) may require a hospital stay or observation. Ask about this beforehand.
During the procedure
You are usually sedated and monitored. The doctor finds the polyp, may inject fluid under it, and removes it with a wire snare, sometimes with an electric current to seal blood vessels. Large polyps may be removed in pieces, and clips may be placed on the area to help prevent bleeding. You should not feel pain from the polyp removal itself. A simple polypectomy takes minutes added to the test; EMR and ESD take longer, with ESD sometimes taking an hour or more.
After the procedure
You will rest until the sedation wears off. Mild cramping, bloating or gas is common. Follow your team’s advice about eating, activity and restarting blood thinners. Take it easy for a day or so, and avoid heavy lifting, long travel and strenuous exercise for the period advised. Bleeding can happen not only on the day but up to a couple of weeks later, as the wound heals. The tissue is examined in the laboratory, and your doctor will tell you when the next surveillance (follow-up) scope is due, based on the findings.
Risks
- Bleeding, during the procedure or up to about two weeks afterward (the most common complication; often treatable with clips or another scope)
- A tear or hole (perforation) in the wall of the bowel or stomach, uncommon, which may need hospital care or surgery
- Pain or discomfort after the procedure, including a rare “post-polypectomy” syndrome with pain and fever
- Reactions to sedation or heart/lung strain, rare
- Not all of a large polyp may be removed, or a follow-up scope or surgery may be needed
- Go to the emergency department now if you have heavy bleeding, passing clots or black stools, severe or increasing belly pain, a swollen hard belly, fever or chills, vomiting, dizziness or fainting.
When you get results
Alternatives if you decline
For many polyps there is no good alternative, because they cannot be treated with medicine. For some large or complex lesions, surgery may be recommended instead of, or after, endoscopic removal. Leaving a polyp in place carries the risk it may grow or become cancer; if you are unsure, discuss the pros and cons with your doctor.
Questions to ask your doctor
Save this list or print it before your appointment — doctors appreciate prepared patients.
- Which technique (polypectomy, EMR or ESD) do you recommend for my polyp, and why?
- Do I need to stop or change any medicines, especially blood thinners?
- Will I need to stay in hospital, and for how long?
- What signs of bleeding should I watch for, and for how many days?
- When will I get the lab results and when is my next scope due?
- Could I need surgery afterwards?
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Status: Approved for publication by SGA; individual clinician review is ongoing · Published 24/04/2026
For general education only; it does not replace your doctor’s advice. Individual clinician review of this guide is ongoing. SGA clinician? Review this guide