Effect of complete pathological response related factors after neoadjuvant chemotherapy on skin-sparing mastectomy and breast reconstruction.

Introduction: Immediate breast reconstruction after skin-sparing mastectomy in patients undergoing neoadjuvant chemotherapy is still controversial. The objective of this study is to determine factors related with axillary downstaging and complete pathological response (CPR), and how CPR influences the decision to perform bilateral mastectomy with immediate reduction.

Methods: A retrospective analysis of breast cancer patients who had undergone neoadjuvant chemotherapy and bilateral mastectomy with immediate reduction between 2000-2018 was performed. Two groups were compared:1) CPR and 2) non-CPR. Descriptive and comparative statistical analyses are provided.

Results: 69 patients; 26 (37.68%) reached CPR and 43 (62.32%) non-CPR. Median follow-up of 45.3 months (IQR: 23.0-94.0). Age under 35 (p <.001), small size tumor at diagnosis (p=.006) and subtype HER2 (p <.001) were associated with higher rates of CPR in bivariate analysis. Axillary negativization rate was 80% in group 1 and 59.3% in group 2, and lymphadenectomy rates were similar (73.1% and 83.72%).

Conclusions: CPR after neoadjuvant chemotherapy did not influence the decision to perform bilateral mastectomy with immediate reduction.