Polypectomy for Colon Polyps: Procedure Overview

What to Expect When Undergoing This Test

Polypectomy is a minimally invasive procedure in which a specialist known as a gastroenterologist removes abnormal tissue growth, called polyps, from inside your colon (large intestine). The procedure is more accurately referred to as a colonic polypectomy.

Polypectomy is a routine part of a procedure known as a colonoscopy in which a long, flexible tube with a camera, called a colonoscope, is inserted into the rectum to view the colon. The aim of a polypectomy is to determine whether an abnormal growth is cancerous, precancerous, or non-cancerous.

Polypectomy is not surgery per se but may be used during surgery if a polyp is too large or complex to be removed during a colonoscopy. The removal of any polyp by either means is still considered a polypectomy.

This article explains the purpose and risks of a polypectomy and what actually occurs before, during, and after this common diagnostic procedure.

Removing a polyp illustration

Purpose of Test

You may need a polypectomy if a polyp is found inside your colon during a routine colonoscopy. On occasion, polyps may be found during an imaging test such as ultrasound, computed tomography (CT) scan, or magnetic resonance imaging (MRI) scan.

Polypectomies are performed by gastroenterologists who are specially trained in various techniques to remove them. The approach varies by the type of polyp involved:

  • Pedunculated polyps are mushroom-like growths attached to the surface of the colon by a long, thin stalk. These are usually easy to remove with an electrical tool called a snare loop.
  • Sessile polyps are flat or dome-shaped masses that arise from the surface of the colon. Smaller ones can often be removed during a colonoscopy, but larger ones can be difficult to remove and require more complicated techniques.

While most polyps are benign, particularly smaller ones, they all theoretically have the potential to turn cancerous. This is especially true of polyps larger than 20 millimeters (3/4 of an inch) that have a 10% chance of being cancerous.

The aim of a polypectomy is to remove abnormal growths so that they can be evaluated in the lab by a pathologist. The pathologist can determine if the growth is benign (non-cancerous), dysplastic (undergoing changes than may lead to cancer), or malignant (cancerous).

Not all polyps can be removed during a colonoscopy. Larger ones may require surgery, either in the form of open surgery (using a scalpel and a large incision) or laparoscopic surgery (using smaller "keyhole" incisions and a specialized narrow scope and tools).

Generally speaking, any polyp that is more than one-third of the interior circumference of the colon needs to be removed surgically.

Risks and Contraindications

A polypectomy may cause bleeding, infection, or bowel perforation. If you take a blood thinner like warfarin, you will typically be advised to temporarily stop the drug prior to the procedure.

If you have an intestinal infection, your healthcare provider will want you to wait until the infection has cleared before you have the procedure. The same is true if you have an active inflammatory bowel condition like ulcerative colitis.

A perforation, in which the bowel is punctured, is a rare complication of polypectomy. If this happens, you will need emergency surgery to repair the colon.

Before the Procedure

Your healthcare provider will usually take the time to explain that a polypectomy may be needed during your colonoscopy.


A polypectomy takes about 20 minutes, but removing several polyps will take longer. You will be given medication that makes you a bit sleepy. Some people will continue to feel groggy from the medication until after a good night's sleep, so be prepared to take it easy for the rest of the day after your procedure.


A polypectomy is generally done in a gastrointestinal (GI) procedure suite that is equipped with a colonoscope, as well as a screen that your healthcare provider uses to visualize the images.

What to Wear

You can dress comfortably. You will be asked to undress from the waist down and to wear a gown throughout your procedure.

Food and Drink

To prepare for a polypectomy, you will be asked to undergo thorough bowel preparation a day or two in advance to ensure that your colon is clear and free of any stool or residue. This can involve the use of a laxative, enema, and a clear food diet. A clear fluid diet includes clear broths, gelatin, and juice (without pulp).

Cost and Health Insurance

In general, most health plans cover colonoscopy and polypectomy, but you may need pre-authorization. If you are paying for the procedure out of pocket, the cost will be in the range of $1,500 to several thousand dollars.

What to Bring

You should be sure to have someone who can drive you home after the procedure, as you may be too groggy to drive safely.

During the Procedure

Your polypectomy will be performed by a gastroenterologist, a healthcare provider who specializes in diseases of the gastrointestinal system. You will also have either an anesthesiologist (who specializes in anesthesia) or a nurse anesthetist assisting with the procedure.


On the day of the procedure, you will have to sign in and fill out forms consenting to the procedure and payment.

The anesthesiologist or the nurse anesthetist will ask if you have any allergies or prior adverse reactions to anesthesia. You will be given a medication to relax you and to make you sleepy, either by mouth or intravenously (IV). You will most likely remain awake in a "twilight sleep" during the procedure, which can take up to an hour.

Once you are prepped and dressed in a hospital gown, you will be laid on your side on the examining table with your knees pulled toward your chest.

Throughout the Procedure

When ready, the healthcare provider will insert a long, flexible colonoscope, which is connected to a camera, into your rectum. You may feel a slight pressure, but it shouldn't hurt. Depending on the room setup, you may be able to see the screen that your healthcare provider is viewing.

Once your healthcare provider locates a polyp, you will have it removed with one of two different types of polypectomies:

  • Snare polypectomy is a technique in which the healthcare provider loops a thin wire (snare) around the base of the polyp and uses heat to simultaneously cut off the growth and cauterize (stop bleeding) the wound.
  • Piece-meal polypectomy is used to remove large growths that would otherwise be removed by surgery. If a person is unable to undergo bowel surgery, this technique removes the growth piece by piece during the course of a colonoscopic procedure. It's rare and reserved only for the biggest polyps, as most polyps are very tiny and can be removed quickly with a variety of techniques.

You may have a local anesthetic injected into the area to prevent pain.

If you have bleeding, your healthcare provider may need to place a suture to stop the bleeding.


After your procedure, your healthcare provider will remove the colonoscope and give you a chance to change and rest. The medical staff will give you instructions explaining what to expect and the symptoms to look out for.

It is not unusual to feel groggy and unsteady on your feet. As such, it is advised that a friend or family member drive you home.

The polyps that were removed are sent to a pathology lab to assess whether there is any sign of colon cancer. Results are usually available within a few weeks.

After the Procedure

While there is usually little pain following the removal of a smaller polyp, pain medication may be prescribed if the removal has been extensive or if your pain is severe. If you did not leave with a prescription but are experiencing pain, call your healthcare provider's office to discuss your symptoms.

Possible Side Effects

In addition to pain, possible side effects of a polypectomy include gas, bloating, cramps, and rectal bleeding. These side effects tend to be mild and usually resolve within 24 hours. You should also avoid driving or using heavy machinery for 24 hours due to the lingering effects of the anesthesia.

The risks of polypectomy are similar to those of the colonoscopy and can include infection and perforation of the bowel. While these complications are considered rare, you should contact your healthcare provider immediately if you experience any of the following symptoms:

  • Fever or chills
  • Heavy bleeding (more than a teaspoon at a time)
  • Severe abdominal pain or bloating
  • Vomiting
  • Lightheadedness, dizziness, or fainting

Interpreting Results

The results of a polypectomy include a report about the type of lesion that was removed, as well as whether the whole lesion was removed or not. The report will also describe whether there were any cancerous or precancerous cells, or whether the tissue was completely normal.

With this, the report will include a description of whether the margins (the edges of the lesion) were normal or whether they contained cancerous or precancerous cells.

When there are areas of concern, normal margins suggest that the concerning areas were fully removed, while margins that contain worrisome cells suggest that the cancerous or precancerous lesions were not fully removed.


A polypectomy does not need to be regularly repeated. However, if there are areas of concern that were not fully removed, your healthcare provider may schedule you for another procedure to remove any remaining lesions or may order follow-up imaging studies.

If there was no evidence of cancer noted on your lab reports, you will need to continue to have routine colonoscopies.


A polypectomy is the removal of abnormal tissue growths known as polyps. A polypectomy is most often performed during a colonoscopy but may be used during surgery if a polyp is exceptionally large or complex.

A polypectomy is used to determine if the abnormal growth is benign, precancerous, or cancerous. While most polyps are benign, all have the potential to turn cancerous, particularly those that are larger.

A polypectomy is performed under light sedation by a gastroenterologist with the assistance of an anesthesiologist. While minimally invasive, the procedure can cause side effects like pain, cramping, gas, bloating, and rectal bleeding, usually mild.

A Word From Verywell

If your colonoscopy report states that no polyps were found, don't presume that to mean that routine colonoscopies are somehow less important.

Some sessile polyps can be difficult to spot higher up in the colon, particularly if they are small. By keeping to the recommended colonoscopy schedule—every 10 years for people 45 to 75 who are at average risk of colon cancer—you can be better assured that any growths can be spotted and removed before they become serious.

Less invasive methods of screening like CT colonography and stool tests are also available, although they need to be repeated every three to five years.

Frequently Asked Questions

  • Is a polypectomy serious?

    A polypectomy is a routine procedure used to assess whether an abnormal growth in the colon is cancerous. Most polyps are not cancerous, but the procedure can catch colon cancer early if it is.

  • Is polypectomy a minor surgery?

    Polypectomy is a minimally invasive procedure typically performed during a colonoscopy. It is not surgery per se but can be performed during surgery if a polyp is too large to be removed during a colonoscopy.

  • How long does it take to recover from polypectomy?

    Recovery from a polypectomy is generally quick, although you shouldn't drive a car or use heavy machinery for 24 hours due to the after-effects of the anesthesia. Side effects like gas, bloating, and cramps tend to be mild and usually resolve within 24 hours.

16 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Julie Wilkinson, BSN, RN
Julie Wilkinson is a registered nurse and book author who has worked in both palliative care and critical care.