A breast biopsy is a procedure to remove a sample of breast tissue for testing. The tissue sample is sent to a lab, where doctors who specialize in analyzing blood and body tissue (pathologists) examine the tissue sample and provide a diagnosis. A breast biopsy might be recommended if you have a suspicious area in your breast, such as a breast lump or other signs and symptoms of breast cancer. It can also be used to investigate unusual findings on a mammogram, ultrasound or other breast exam.