Nadia Harbeck, MD, PhD, Ludwig Maximilian University of Munich, Munich, Germany, discusses the predicative impact of biomarkers on pathological complete response (pCR) and survival in patients HER2+/HR+ early breast cancer. In the WSG TP phase II-trial, part of the ADAPT umbrella (NCT01779206), 375 patients received trastuzumab emtansine with or without endocrine therapy (ET), or trastuzumab with ET. Tumor-infiltrating lymphocytes (TILs) were not predicative of invasive disease-free survival (iDFS), whereas tumor immunogenicity was associated with improved outcomes. This interview took place at the European Society for Medical Oncology (ESMO) 2021 congress.