Oncologic Safety of Nipple-Sparing Mastectomy in Patients with Breast Cancer and Tumor-to-Nipple Distance ≤ 1 cm: A Matched Cohort Study.

Background: A short tumor-to-nipple distance (TND) is reported as a strong predictor of nipple-areola complex (NAC) involvement. Eligibility for nipple-sparing mastectomy (NSM) remains controversial, especially regarding TND. In this study, we compared long-term oncologic outcomes after NSM between patients with a TND ≤ 1 cm and those with a TND > 1 cm.

Methods: Overall, 1369 patients with primary breast cancer who underwent NSM with immediate reconstruction from March 2003 to December 2015 were included for analysis. After propensity score matching, 495 patients with a TND ≤ 1 cm (group A) and 495 patients with a TND > 1 cm (group B) on imaging were selected to compare long-term oncologic outcomes.

Results: After matching, the median follow-up periods for surviving patients were 109 months and 112 months for groups A and B, respectively. There were no significant differences between groups with respect to the 5-year cumulative local recurrence (8.1% vs. 6.3%; p = 0.268), NAC recurrence (5.1% vs. 2.8%; p = 0.072), regional recurrence (2.0% vs. 3.6%; p = 0.125), or distant recurrence (5.9% vs. 4.8%; p = 0.480) rates. Furthermore, no significant differences were observed between the groups with respect to the 10-year local recurrence-free survival (87.1% vs. 90.7%; p = 0.164) or disease-free survival (77.9% vs. 81.6%; p = 0.222) rates.

Conclusions: A preoperative TND ≤ 1 cm on imaging should not be contraindicated to NSM as long as there is no involvement of NAC clinically or on imaging and if retroareolar margins are confirmed to be negative for tumor cells.