ASCO 2020: highlights in breast cancer

The 2020 Annual Meeting of the American Society of Clinical Oncology (ASCO) was held in a virtual format due to the ongoing SARS-CoV-2 pandemic. Despite these unique circumstances, results of several interesting studies in the field of breast cancer (BC) were reported. While overall survival data are still missing, KEYNOTE-355 suggests significant activity of pembrolizumab when added to first-line chemotherapy in metastatic triple-negative breast cancer. TBCRC 048 evaluated the role of olaparib in homologous recombination deficient tumours due to genomic alterations other than germline BRCA1/2 mutations; clinically relevant activity was reported in patients with germline PALB2 and somatic BRCA1/2 mutations. In HER2-positive early stage disease, different strategies of chemotherapy de-escalation are under investigation, but the optimal approach is still not well defined. Updated results from the HER2CLIMB trial show that the third-generation HER2 tyrosine-kinase inhibitor tucatinib in combination with trastuzumab and capecitabine is the new standard-of-care for pretreated patients with HER2-positive metastatic BC with active brain metastases. Results from BYLieve supports the notion that the combination of endocrine therapy with the PIK3Ca inhibitor alpelisib is a reasonable treatment approach in hormone-receptor positive/HER2-negative BC after prior CDK4/6-inhibitor therapy. Finally, the ECOG-ACRIN 2108 trial failed to show a benefit for early surgery of the primary tumour in patients with metastatic BC.

Automated summary

The 2020 ASCO Annual Meeting highlighted several interesting studies in the field of breast cancer, including significant activity of pembrolizumab in metastatic triple-negative breast cancer, the role of olaparib in homologous recombination deficient tumors, different strategies of chemotherapy de-escalation in HER2-positive early stage disease, and the new standard-of-care using tucatinib in combination with trastuzumab and capecitabine for HER2-positive metastatic breast cancer with brain metastases.