biopsy -- detailed

Alternative Names 
tissue sample

Definition
A biopsy is the removal of a sample of tissue from the body. The sample is then examined under a microscope. Biopsies are used to diagnose many medical conditions, from skin problems to cancer.

Who is a candidate for the test? 
Anyone whose medical condition needs a specific diagnosis may need a biopsy. A biopsy may also be needed to monitor a disease or condition.

How is the test performed? 
There are several different kinds of biopsy.

In an excisional biopsy, a whole organ or whole lump is removed by surgery. This may require general anaesthesia. General anaesthesia means that a person is put to sleep with medications and feels no pain. This kind of biopsy is often used to diagnose cancer.

For an incisional biopsy, the surgeon cuts out a small piece of the tissue or lump. This may require general or local anaesthesia. Local anaesthesia means that medication is injected locally in an area to numb it, but the person stays awake. This kind of biopsy is used to diagnose some cancers. It is also used to tell the difference between normal and diseased tissue.

A punch biopsy takes a small piece of skin using a sharp punch tool. The punch only cuts through the top layers of skin. The skin is cleaned and numbed first with local anaesthesia or topical anaesthesia. A punch biopsy is used to diagnose skin conditions.

In a needle biopsy, a needle is inserted through the skin into the tissue. Tiny amounts of tissue are then sucked out through the needle. This is usually done under local anaesthesia. This kind of biopsy is used to diagnose liver problems, thyroid disease, and breast cancer. It is also used for other conditions, especially tumours in organs that are hard to reach.

In a bone marrow biopsy, a needle is inserted into a bone, usually the hip bone, or pelvis. Bone marrow cells are sucked out of the inside of the bone. This sometimes causes moderate pain. This kind of biopsy is usually done under local anaesthesia. It is used to diagnose leukaemia, other cancers, and low blood counts in some situations.

An endoscopic biopsy uses an endoscope, a lighted, flexible tube, to get the tissue. The endoscope can be inserted through the skin with local anaesthesia. It can also be inserted into the bowel from the top or bottom. An endoscope can be inserted into the lungs, bladder, or uterus, as well. The endoscope is used to find the abnormal tissue. Then, a tiny tool can be placed through the endoscope. The tool can take a small piece of the abnormal tissue. Endoscopic biopsy can be used to diagnose many different diseases and conditions.

A colposcopy-directed biopsy uses a colposcope, which is a special microscope for examining the cervix. The cervix is the lower part of the uterus that connects to the vagina. This kind of biopsy usually requires no anaesthesia. It is used to collect abnormal tissue from the cervix. It is usually done after a woman has an abnormal Pap smear.

In a stereotactic biopsy, special X-ray tests are used to guide the doctor. This allows the doctor to insert a biopsy needle into the abnormal area. It is used when the abnormal tissue cannot be seen or felt directly, and helps make sure that abnormal tissue is taken. It is often used when abnormalities are found on X-ray tests, such as mammography or a CT scan.

What is involved in preparation for the test? 
Usually no special preparation is needed. The doctor will give any special instructions. A person can't eat or drink for several hours before general anaesthesia.

What do the test results mean? 
It may take several days for the results to come back. The doctor will discuss the results and what they mean.

Author: 
Reviewer: eknowhow Medical Review Panel
Editor: Dr John Herane

Last Updated: 23/09/2004
Contributors
Potential conflict of interest information for reviewers available on request