Abstract P2-18-08: Nipple-sparing mastectomy for patients with multifocal breast cancer

Introduction: Cosmetic outcome is one of the most important goals of surgical treatment for breast cancer. Therefore, to maximize the cosmetic outcome for patients who require a mastectomy, the actions that can be taken from an oncologically safe perspective must be considered. Recent reports have suggested that nipple-sparing mastectomy (NSM) is oncologically as safe as a standard mastectomy and provides a better cosmetic outcome. However, little is known about the outcome of NSM for patients with multifocal breast cancer. Aim: To determine the oncological and technical outcomes of NSM for patients with multifocal breast cancer compared with NSM for patients with unifocal breast cancer using retrospective long-term follow-up data. Patients and Methods: We retrospectively analyzed 799 patients with primary breast cancer who underwent NSM, including 45 patients with multifocal breast cancer and 754 patients with unifocal breast cancer. The indications for NSM in this study were defined as any stage, any tumor size and any tumor–areola distance. Briefly, NSM was performed when no involvement of the nipple areola complex was revealed by radiographic and clinical examinations. Our surgical notes for NSM comprised a thick skin flap method for conserving the breast volume using subcutaneous fat and avoiding surgical complications including nipple necrosis. No patients received radiotherapy. We compared the local recurrence rate (LRR), disease-free survival (DFS), breast cancer-specific survival (BCSS) and overall survival (OS) between the 45 multifocal breast cancer and 754 unifocal breast cancer cases. Results: The numbers of multifocal breast cancer cases in stages 0, 1, 2A, 2B, 3 and 4 were 1, 17, 12, 8, 7 and 0, respectively. The corresponding numbers of unifocal breast cancer cases were 18, 288, 223, 117, 102 and 6, respectively. The median follow-up periods of the multifocal and unifocal breast cancer cases were 108 and 98 months, respectively. No nipple necrosis was recorded in either group (0/45, 0/754). Regarding NSM for patients with multifocal breast cancer, there were 8 patients (17.7%) with local recurrence, including 4 (8.9%) at the nipple and 4 (8.9%) at the skin flap. In NSM for patients with unifocal breast cancer, there were 63 patients (8.3%) with local recurrence, including 26 (3.4%) at the nipple and 37 (4.9%) at the skin flap. There were significant differences between NSM for patients with multifocal and unifocal breast cancer in the LRR (17.7% vs. 8.3%, p = 0.03) and DFS (10 yr, 72.4% vs. 83.8%, p = 0.04), but no significant differences in the BCSS (10 yr, 83.6% vs. 90.9%, p = 0.18) and OS (10 yr, 83.6% vs. 89.5%, p = 0.32). Conclusions: The present results suggest that NSM for patients with multifocal breast cancer can be technically performed as safely as NSM for patients with unifocal breast cancer. Our long-term follow-up data show that survival after NSM for multifocal breast cancer is equal to that after NSM for unifocal breast cancer. However, careful local observation after NSM is required. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-18-08.