A breast biopsy is a diagnostic procedure used to collect samples of breast tissue for examination under a microscope by a pathologist. Two types of breast biopsies are used to extract tissue samples. They are Stereotactic Breast Biopsy and Ultrasound-Guided Breast Biopsy.

Stereotactic Breast Biopsy is prescribed when an X-ray of the breast tissue called a Mammogram shows a mass, a cluster of microcalcifications, or an area of abnormal tissue without necessarily feeling a lump during a careful breast examination. Ultrasound Guided Breast Biopsy is prescribed when suspicious masses within the breast are visible on ultrasound.

Stereotactic breast biopsy is a minimally invasive procedure that uses special three-dimensional computerized imaging to pinpoint suspicious areas in the breast so that tissue samples may be withdrawn with a needle. Ultrasound-guided breast biopsy is an alternate procedure that uses sound waves to pinpoint suspicious areas in the breast.

In either procedure, a biopsy needle is used to remove samples of tissue for examination. An inner needle with a trough extending from it at one end is covered by a sheath and attached to a spring-loaded mechanism. When the mechanism is activated, the needle moves forward, filling the trough with breast tissue. The outer sheath instantly moves forward to cut the tissue and keep it in the trough. It takes only a fraction of a second to obtain a sample. For each sample it is necessary to withdraw the needle to collect the tissue. Tissue is obtained in an orderly manner by rotating the needle, ensuring that the entire region of interest will be sampled.

Regular mammograms as prescribed by your doctor are excellent to detect breast abnormalities. However, it is not always possible to tell from a mammogram alone whether an abnormality is benign or cancerous. To make this determination it is necessary to obtain a tissue sample for microscopic examination by a pathologist. Stereotactic and ultrasound-guided biopsies are alternatives to open surgical biopsy, which removes a larger specimen for microscopic analysis. These procedures are much less invasive than surgery and the sample of breast tissue obtained in this way is generally enough to show whether cancer is present.