All patients receive technetium (Tc 99m) sulfur colloid injected into normal breast tissue within 1 cm of the primary tumor or biopsy cavity and an intradermal injection of technetium (Tc 99m) sulfur colloid, approximately 0.5-8 hours before surgery. Patients also receive an injection of isosulfan blue dye around the tumor or biopsy cavity after a hot spot is identified with a gamma detector. If a hot spot is not identified, the blue dye is injected after a saline bolus injection.