A special mammographic machine produces digital images to guide precise needle biopsy (sampling of cells or tissue) of a questionable area.  This procedure often avoids the need for an open surgical biopsy.

The benefits of stereotactic breast biopsy, compared to surgical excisional biopsy, include:

• Accuracy similar to excisional biopsy.
• Decreased patient discomfort and recovery.
• No cosmetic defect of the breast.
• No distortion of the breast tissue that might make interpretation of future mammograms difficult.
• Decreased cost.

• Not all lesions can be biopsied (see "patient selection" below).
• The lesion is not completely removed (some patients require complete removal for peace of mind).
• The pathologic diagnosis is occasionally indeterminate and excisional biopsy would still be required.