Which diagnostic procedure involves removal of living tissue from the body for diagnostic examination?

• A. Blood urea nitrogen (BUN)
• B. Biopsy
• C. Bone scan
• D. Bronchoscopy

Answer: (B)

Removing living tissue for diagnostic examination is called a biopsy. This procedure provides a small sample that a pathologist can examine under a microscope to identify diseases, most commonly cancer, but also infections or inflammatory conditions. Biopsies can be done in many ways—such as needle, punch, incisional, excisional, or during endoscopic procedures—depending on where the disease is suspected. In contrast, a blood urea nitrogen test measures waste products in the blood to assess kidney function and does not involve sampling tissue. A bone scan uses a radioactive tracer to image bone metabolism and detect abnormalities, which is an imaging study rather than tissue sampling. A bronchoscopy allows viewing the airways and can include obtaining tissue samples, but the procedure that specifically denotes removal of tissue for diagnostic examination is biopsy.