P124. Avoiding Surgery in Breast Cancer Patients with Exceptional Response to Neo-Adjuvant Chemotherapy - ASTARTE Trial

Background: Neoadjuvant chemotherapy (NACT) is increasingly used in phenotype-appropriate, early-stage breast cancer. Modern chemotherapy regimens and the use of targeted therapies can eliminate gross disease in an increasing number of women. Particularly in triple negative (TN) and HER2-positive subtypes, pathologic complete response (pCR) rates exceeding 60% have been reported. In these cases, the role of surgery is limited to histopathological confirmation of pCR. Recent data suggest that in selected women with exceptional clinical and imaging response, post-NACT, pre-surgery large volume, vacuum-assisted core biopsy (VACB) of the imaging residuum can reliably identify those who achieve pCR and therefore may not benefit from surgery. ASTARTE is a pilot study aiming to evaluate the safety of omission of surgery in a selected group of women with exceptional response to NACT.