An Innovative Scoring System to Select the Optimal Surgery in Breast Cancer after Neoadjuvant Chemotherapy.

INTRODUCTION: The selection of surgery post-neoadjuvant chemotherapy (NACT) is difficult and based on surgeons' expertise. The aim of this study was to create a post-NEoadjuvant Score System (pNESSy) to choose surgery, optimizing oncological and aesthetical outcomes.

METHODS: Patients (stage I-III) underwent surgery post-NACT (breast-conserving surgery (BCS), oncoplastic surgery (OPS), and conservative mastectomy (CMR) were included. Data selected were BRCA mutation, ptosis, breast volume, radiological response, MRI, and mammography pre- and post-NACT prediction of excised breast area. pNESSy was created using the association between these data and surgery. Area under the curve (AUC) was assessed. Patients were divided into groups according to correspondence (G1) or discrepancy (G2) between score and surgery; oncological and aesthetic outcomes were analyzed.

RESULTS: A total of 255 patients were included (118 BCS, 49 OPS, 88 CMR). pNESSy between 6.896-8.724 was predictive for BCS, 8.725-9.375 for OPS, and 9.376-14.245 for CMR; AUC was, respectively, 0.835, 0.766, and 0.825. G1 presented a lower incidence of involved margins (5-14.7%; p = 0.010), a better locoregional disease-free survival (98.8-88.9%; p < 0.001) and a better overall survival (96.1-86.5%; p = 0.017), and a better satisfaction with breasts (39.8-27.5%; p = 0.017) and physical wellbeing (93.5-73.6%; p = 0.001).

CONCLUSION: A score system based on clinical and radiological features was created to select the optimal surgery post-NACT and improve oncological and aesthetic outcomes.