ESMO 2020: highlights in breast cancer

Area of Science:

• Medical Oncology
• Clinical Trials
• Breast Cancer Research

Background:

• The 2020 European Society of Medical Oncology (ESMO) Congress presented key breast cancer (BC) study results during the SARS-CoV-2 pandemic.
• Advances in adjuvant therapies and treatments for metastatic breast cancer were highlighted.

Purpose of the Study:

• To summarize pivotal clinical trial findings in early-stage and metastatic breast cancer presented at ESMO 2020.
• To evaluate the efficacy of novel therapeutic strategies including CDK 4/6 inhibitors, immunotherapy, and antibody-drug conjugates (ADCs).

Main Methods:

• Review of results from key clinical trials including MonarchE, PALLAS, ADAPT-TP, IMpassion031, IMpassion130, and ASCENT.
• Analysis of treatment effects on recurrence rates, pathological complete remission, progression-free survival, and overall survival in diverse breast cancer subtypes.

Main Results:

• MonarchE trial suggests abemaciclib addition to endocrine therapy reduces recurrence in high-risk early-stage HR+/HER2- BC, while PALLAS did not confirm palbociclib benefits.
• ADAPT-TP trial supports chemotherapy-free options for HER2-positive early-stage BC with favorable response to HER2-directed therapy.
• IMpassion031 showed improved pathological complete remission with atezolizumab in neoadjuvant TNBC; IMpassion130 confirmed OS benefit of atezolizumab with nab-paclitaxel in metastatic PD-L1+ TNBC.
• ASCENT trial demonstrated improved PFS and OS with sacituzumab govitecan compared to chemotherapy in pretreated metastatic TNBC.

Conclusions:

• CDK 4/6 inhibitors show potential in adjuvant settings for specific early-stage breast cancer populations, though results vary.
• Immunotherapy, particularly atezolizumab, demonstrates efficacy in specific subtypes of triple-negative breast cancer, both in neoadjuvant and metastatic settings.
• Antibody-drug conjugates like sacituzumab govitecan represent a promising new standard of care for pretreated metastatic triple-negative breast cancer.