Surgical technique of the matrix rotation.

The non-donut method was employed for those tumors which could be resected by a reverse-triangular shaped en bloc resection with negative margins (A). A concave incision was made along the lateral border of the breast from the tumor site to the midaxillary line, followed by a small triangular-shaped incision in the axilla to facilitate lymph node management and subsequently flap advancement (B). For tumors located less than 3 cm away from NAC or if safety margins could not be obtained by non-donut en bloc resection (C), the donut method was used which involved periareolar de-epithelialization and en bloc resection in a rectangular shape (D and E).