What to Expect From a Colon Biopsy

A colon biopsy is a diagnostic procedure that includes the removal and examination of a tissue sample from the colon. It is usually used to determine whether any of the tissue cells are cancerous or precancerous, and is sometimes done during a diagnostic process for inflammatory bowel diseases.

Getting sent for a colon biopsy does not mean that you have cancer. It simply means that your healthcare provider thinks that the information the biopsy can provide would help determine the cause of any symptoms. A biopsy may also be done if an area of the colon appears abnormal.

An illustration with signs you may need a colon biopsy

Illustration by Lara Antal for Verywell Health

Purpose of a Colon Biopsy

A colon biopsy is done so that your healthcare provider will be able to assess the microscopic characteristics of the tissue in your colon—this includes changes In the cells, inflammation, and potentially certain infections.

You may need a biopsy if you are experiencing certain signs or symptoms or if other testing indicates areas of suspicion.

Symptom Investigation

A biopsy may be done if you are experiencing any of the following symptoms:

Evaluating Areas of Suspicion

Imaging tests can often provide helpful information about the health of the colon, but sometimes more invasive tests are needed.

A colonoscopy is an invasive diagnostic test that allows your provider to visualize the inner lining of the colon with a camera. This test is done as a routine screening for colon cancer, and it can also be done to evaluate symptoms.

A colon biopsy will typically be taken from an area in the colon that appears abnormal on an imaging test or a colonoscopy.

Risks and Complications

A colon biopsy is generally a safe procedure that doesn't require a recovery time.

In some rare cases, however, infection or injury has been known to occur.

Before the Test

A day prior to the procedure, you will be instructed to restrict your diet to things like clear broth and gelatin in order to ensure that the colon is completely evacuated and free of any obstructions that can interfere with viewing.

You will be prescribed a strong laxative in order to ensure the bowels are clear of any fecal matter. An enema may also be provided to help remove residual matter.

To some people, this is the most unpleasant part of the procedure since it involves repeated trips to the toilet and sometimes explosive rushes of runny stools or fluid.

There is little actual pain or discomfort during the cleaning-out stage, although minor cramping may occur.

You might also be asked to stop taking blood thinning medications or other medications that can affect your colon (for example, antibiotics or anti-inflammatories).

During a Colon Biopsy

When you arrive for your biopsy, you will be asked to sign a consent form.

A healthcare provider will escort you to a pre-procedure room and ask you to change into a gown. Your vital signs will be checked and an intravenous (IV) line will be placed.

Throughout the Test

An anesthetist will give you a sedative medication. You will likely sleep during your procedure, and you won't be able to feel any pain or discomfort.

You will be laid on your side on the examining table with your knees pulled toward your chest.

A colonoscopy is the standard method for performing a colon biopsy. It involves the use of a four-foot-long, flexible tube, called a colonoscope, which is inserted into the rectum while the person is under sedation. The colonoscope is equipped with a light, a camera, and a specialized device used to snip tissue samples.

Most colon cancer starts as a benign growth called a polyp. Although some polyps look more suspicious than others (because of their color, texture, or size), a biopsy would be performed on each polyp just to be safe. Any other tissue in the colon that looks suspicious will also be sampled.

The procedure takes between 20 minutes to one hour.

Post-Test

When your procedure is complete, you will go to a recovery area for a short time, and you should be able to go home afterward if you are feeling fine.

You will need someone to drive you home since you might feel groggy from the anesthesia. You can continue your day as usual when you feel up to it, but you might want to sleep for a few hours.

After the Procedure

While the idea of having a piece of your colon removed may seem unsettling, you'll be happy to learn that most people don't even feel any discomfort. The biopsy is taken from the innermost lining of your colon (called the mucosa),which isn't particularly sensitive to pain.

Once home, you may experience some gas or mild cramping, but typically nothing serious.

Call 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 pain or bloating
  • Vomiting
  • Irregular heartbeats (arrhythmia)

Getting Your Colon Biopsy Results

Once the biopsy is sent to the lab, you should expect to receive the results within a week.

If there is any abnormality, your healthcare provider will make recommendations about follow-up testing and/or treatment. Sometimes a polyp is found to be completely normal and no further treatment is needed.

If there is any evidence of cancer, your provider will schedule other tests to determine how aggressive it is and whether it started in your colon or has spread from other parts of the body. These evaluations will be used to determine the best course of treatment moving forward.

3 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.
  1. Cancer Treatment Centers of America. Colorectal Cancer Symptoms.

  2. The American Cancer Society. Colorectal Cancer Screening Tests. Last revised May 30, 2018.

  3. The American Cancer Society. Tests to Diagnose and Stage Colorectal Cancer. Last revised August 10, 2018.

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