Breast-Conserving Surgery With Partial Nipple-Areola Resection Based on Mammary Gland Anatomy

The nipple-areola complex (NAC) is generally resected to treat breast cancer in or near the nipple-areola (NA) region. Embryologically, each glandular lobe system is independent until the ductal opening on the nipple surface. Thus, the nipple can be preserved by partial excision, including the collecting duct occupied by the intraductal extension of breast cancer. We aimed to demonstrate that NAC preservation by partial NA excision is feasible in early-stage breast cancer with intraductal extension into the NA region.

The participants in this surgery were patients with breast cancer in stages 0-IIA who were classified into the following three groups. Space-occupying lesions were defined as primary lesions. The main lesion was located outside the NA region, accompanied by intraductal extension within the NA region (39 patients). The main lesion partially extended to the subareolar area and was accompanied by intraductal extension within the NA region (13 patients). The main lesion partially extended to the subareolar area but was not accompanied by intraductal extension within the NA region (four patients). The degree of intraductal extension toward the nipple was determined using preoperative contrast-enhanced magnetic resonance imaging with the patient in the prone position. Diagnoses were based on the pathological results of the postoperative resection specimens. Breast-conserving surgery was performed via quadrantectomy of the nipple and the region under the nipple, with the addition of full-layer excision of the areolar region, including the target duct, and further resection, including the main lesion.

The excised portion resembled an entire cake-cut. Four patients had positive resection margins in the NA region. Postoperative pathological examination revealed no intraductal extension under NAC in eight patients. Deformation of the NAC was minor.

This approach may be suitable for NAC-sparing procedures.