A biopsy is a procedure that removes a small amount of tissue for examination in a laboratory. Biopsies are done 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 accompanied 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 a 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.
Endoscopy procedures — An instrument attached to the end of an endoscope, such as those used in bronchoscopy or colonoscopy, is used to remove a tissue sample.
Biopsies can take as little as a minute for a simple skin biopsy or up to an hour or more for deep biopsies.