Data presented at ASCO 2022 provide new perspectives of therapy for patients with breast cancer.
Starting with the plenary session with DESTINY-Breast04 we are turning a new page in the treatment of metastatic human epidermal growth factor receptor 2 (HER2)-low breast cancer patients. The results of the DESTINY-Breast04 trial open a new therapeutic option for half of the patients with metastatic breast cancer, establishing HER2-low metastatic breast cancer as a targetable population with trastuzumab deruxtecan. The indications for antibody drug conjugates are expanding to patients with metastatic hormone receptor positive endocrine resistant disease based on TROPICS-02. From the multitude of clinical trials with antibody drug conjugates, we can envision that this will be likely the new way to deliver chemotherapy in the future.
Differences in survival within the three cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in upfront metastatic hormone positive breast cancer are emerging. We have data on continuation of ribociclib beyond disease progression on CDK4/6 in the MAINTAIN trial. The FAKTION trial does prove the benefit of the AKT inhibitor capivasertib and does highlight the importance of an extended molecular panel of the phosphatidylinositol3-kinase PI3K pathway.
Furthermore, the exploratory analysis of KEYNOTE- 522, examining the correlation of event free survival and residual cancer burden after neoadjuvant treatment in patients with triple negative breast cancer does demonstrate a benefit of pembrolizumab extending to patient which did not achieve pathologic complete response, mainly by a decrease in residual cancer burden. Advances in biomarkers of response to immunotherapy are needed.
For early stage breast cancer studies are in support of de-escalation of radiotherapy for low risk breast cancer patients and confirming the lack of benefit of adjuvant chemotherapy for elderly patients, even with high genomic grade index.