A polyp biopsy is a diagnostic procedure that takes a sample of or removes polyps (abnormal growths) for examination.

The test is performed to determine if the growth is malignant (cancer).

Polyps are outgrowths of tissue that may be attached by a stalk-like structure (a pedicle). They are commonly found in organs with many blood vessels, such as the uterus, colon, and nose. Some polyps are cancerous (malignant) and likely to spread, while others are noncancerous (benign).

How a polyp biopsy is taken depends on the location:

• EGD (esophagogastroduodenoscopy) or other endoscopy is used for the throat, stomach, and small bowel.
• Colonoscopy or flexible sigmoidoscopy explores the large bowel.
• Colposcopy-directed biopsy examines the vagina and cervix.

For areas of the body that are visible, a topical anesthetic is applied, and a small piece of the tissue that appears to be abnormal is removed. This tissue is sent to the laboratory, where technicians determine if the polyp is benign or malignant.

If the biopsy is to take place in the nose, or other visible surface or orifice, no special preparation is required, although fasting for a few hours beforehand may be advisable.

There is more preparation needed for internal procedures. Please see the particular procedure for additional information.

For superficial polyps, you may feel a tugging sensation while the biopsy is being taken. After the anesthetic wears off, the area may be sore for a few days. Biopsies of internal polyps are performed during procedures (for example EGD or colonoscopy), and usually nothing is felt during or after the biopsy. Please see the individual procedure topics for more specific information.