Migration of localizing wires used in guided biopsy of the breast.

Inadvertent retraction of a localizing wire into the breast occurred in three of a series of 158 localizations prior to biopsy for an impalpable mammographic abnormality. In each case retraction was followed by migration into the subcutaneous tissues and/or spontaneous extrusion. A wire inserted for localization prior to guided biopsy of the breast should be left long and secured externally to prevent retraction.