In breast conservative surgery the healthy margin excised in typically?

In Conservative breast surgeries Wide local excision is preferred. It is the removal of unicentric tumour with 1cm clearance margin. Incision is made directly over the tumour. At least 1mm clearance is needed for adequacy. Margins where clearance is less than 1mm need reexcision at that paicular site. If margins show no clearance then patient requires probably total mastectomy. Reference: SRB's Manual of Surgery, 6th Edition, page no = 540.