ASCO 2021 featured one crucial, practice-changing trial in early breast cancer: the OlympiA trial showed that one year of adjuvant olaparib improves invasive disease-free survival by 8.8% compared to placebo, when administered to high risk early breast patients (triple negative or hormone sensitive and HER2 negative) with a germline BRCA1 or 2 mutation. Furthermore, ECOG-ACRIN EA1131 failed to show improved outcome in triple negative breast cancer treated without pathological complete response after neoadjuvant chemo-therapy with platinum based chemotherapy compared to the current standard capecitabine. GeparNUEVO for the first time showed long term outcome with anti-PD(L)1 therapy administered with neoadjuvant chemotherapy in triple negative breast cancer. In the advanced setting, interesting overall survival updates of the PALOMA-3 and MONALEESA-3 studies were presented. Furthermore, the SYsucc-002 trial demonstrated that trastuzumab plus endocrine therapy was non-inferior to and had fewer toxicities compared with trastuzumab plus chemotherapy in patients with HR+/HER2- metastatic breast cancer. In addition, this article will touch upon several other studies that are notable.

(BELG J MED ONCOL 2021;15(5):208-17)