Minimally Invasive Biopsy Predicting Breast pCR After NAC for Breast Cancer

In clinical routine surgical treatment follows the neoadjuvant chemotherapy (NAC). However, recent studies have demonstrated that shrinking tumors need less surgical treatment indicating that patients with pCR could potentially be spared of surgery in the future. However, up to now, prediction of pCR after NACT is only moderately accurate. This prospective, monocenter diagnostic trial aims to explore if minimal invasive biopsies (MIB) might overcome this diagnostic challenge. From June 1st, 2017 to June 15th, 2019 the investigators performed ultrasound-guided multipoint core needle biopsy (CNB) on 50 breast cancer patients after NAC and directly after surgery. To analyse CNB pathologically results were categorized as follows: residual vital tumor cells (invasive, in situ, both, lymphangiosis carcinomatosous) present, (significant parts of) the tumor bed present, neither vital tumor cells nor (significant parts of) the tumor bed (indicating a non representative VAB). The results were compared to those of the pathological examination of surgical specimen.