Biopsy

What Is It?

A biopsy is a procedure that removes a small amount of tissue for examination in a laboratory. Biopsies are performed to diagnose many diseases, especially cancer. In some cases, biopsies help to determine prognosis and appropriate treatment. There are different biopsy techniques, depending on which tissue or organ is being sampled.

• Skin biopsy — A sample of skin tissue is removed with a scalpel or punch tool.
• Fine-needle aspiration — A very thin needle is inserted into an organ. Often the procedure is acccompanied by ultrasound or computed tomography (CT) scanning to make sure that the needle is in the correct location. The needle is attached to a syringe. The doctor pulls back on the plunger to suck cells from the organ into the empty syringe. The cells are spread on a slide and sent to the laboratory.
• Core needle biopsy — A larger needle with a cutting edge is used to take a full tissue sample, rather than just sucking out cells. A core biopsy gives more information than a fine-needle biopsy.
• Open biopsy — Requires an incision in the skin. Depending on the depth of the body part to be biopsied, the complexity of the procedure varies. For example, a biopsy of an enlarged lymph node in the neck requires only a local anesthetic and often can be done in a doctor's office. Open biopsy of a lung or abdominal structure has to be done in an operating room under general anesthesia. Biopsies can take as little as a minute for a simple skin biopsy or up to an hour or more for deep biopsies.
• Endoscopy procedures — An instrument attached to the end of anendoscope, such as those used in bronchoscopy or colonoscopy, is used to remove a tissue sample.

What It's Used For

A biopsy procedure removes sample bits of tissue or cells to be checked in the laboratory for microscopic signs of cancer or other diseases. In the lab, the biopsy sample is stained and examined under the microscope. This examination can tell whether the tissue sample is normal, not cancerous (benign) or is cancerous (malignant). The laboratory examination can identify the type of cancer, and may be used to evaluate the chance that cancer has spread to other parts of the body. For some types of cancer, new laboratory techniques test biopsy samples for other features of the cells, such as genetic changes. This information can be used to make a more precise diagnosis and plan more individualized therapy.

A biopsy also can identify the causes of inflammations and infections.

Preparation

Because there are several different types of biopsy procedures, your preparation will depend on your specific biopsy. For a skin biopsy, for example, you usually won't need to modify your diet beforehand. However, for an open biopsy that requires general anesthesia, you will need to stop eating and drinking at least several hours before the procedure. If you are scheduled for a colonoscopy and possible colon biopsy, you will take laxatives and enemas according to your doctor's directions, and will have to modify your diet.