Nearly a decade after the first presentation of landmark trials demonstrating survival benefit from response-driven adjuvant chemotherapy for TN and HER2+ breast cancer following NAC (CREATE-X and KATHERINE), our analysis was needed to explore factors underlying the slow uptake of NAC in practice (particularly important now, given the upholding of the KATHERINE trial’s initial findings and demonstration of improved overall survival in its most recent 2023 update) [9,10,39,40,58]. Here, ERBB2 is linked to breast cancer.