What is a biopsy? A biopsy is the removal of a sample of tissue from the body for examination. The tissue will be examined under a microscope to assist in diagnosis. Therefore, only very small samples are needed. Sometimes, it's enough just to scrape over an area. This is the case with smear examinations of the cervix (neck of the womb). During examination of the large intestine, a biopsy can be taken with forceps through a tube known as an endoscope. In other cases, for instance, a liver or kidney biopsy, the biopsy is taken using a large hypodermic needle. To diagnose the presence of cancer, a doctor must look at a sample of the affected tissue under the microscope. Hence, when preliminary symptoms, Pap test, mammogram, PSA test, FOBT, or colonoscopy indicate the possible existence of cancer, a doctor must then perform a biopsy for microscopic examination. This microscopic examination will tell the doctor whether a tumor is actually present and, if so, whether it is malignant (i.e., cancer) or benign. In addition, microarrays may be used to determine which genes are turned on or off in the sample, or proteomic profiles may be collected for an analysis of protein activity. This information will help doctors to make a more accurate diagnosis and may even help to inform treatment planning. source 1:Biopsy source 2:www.cancer.gov
