A biopsy (in Greek: bios = life and opsy = look/appearance) is a medical test involving the removal of cell or tissue for examination. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically (for example, using PCR or gas chromatography techniques). When only a sample of tissue is removed, the procedure is called an incisional biopsy or core biopsy. When an entire lump or suspicious area is removed, the procedure is called an excisional biopsy. When a sample of tissue or fluid is removed with a needle, the procedure is called a needle aspiration biopsy. After the biopsy is performed, the sample of tissue that was removed from the patient is sent to the pathology laboratory. A pathologist is a physician who specializes in diagnosing diseases (such as cancer) by examining tissue under a microscope. When the laboratory receives the biopsy sample, the tissue is proce