A biopsy is a test for cancer. The only certain way to learn if your breast lump or abnormality seen in a mammogram is cancerous is to remove part or all of the suspicious tissue and to examine it under a microscope. A pathologist will determine if the tissue is benign (not cancerous) or malignant (cancerous).

If the tissue is malignant, the pathologist will try to determine the type of cancer cells, how fast they reproduce, and whether the growth is affected by hormones that your body produces.

All of this information allows you and your health care provider to pick the best treatment for you. There are several different needle and surgical biopsy procedures.

The dot line shows where the biopsy will take place.