Needle biopsies are performed to gather a sample of suspicious tissue for testing by a pathologist. This is often performed to finalize a diagnosis and determine a tumor type. The procedure is performed with imaging (such as x-ray imaging, also called fluoroscopy) to guide the physician to the correct location. A needle is then inserted to extract a tissue sample, which is sent for testing. Most biopsies are performed with local anesthetic and sedation on an outpatient basis.