ABSTRACT
This chapter discusses the latest developments in molecular and targeted therapies for the treatment of breast cancer, both in the curative and metastatic settings. In the neoadjuvant setting, the use of trastuzumab and dual HER2 blockade has shown significant improvement in the pathological complete response rates as well as the event-free survival for patients treated with neoadjuvant chemotherapy. Risk prediction tools, such as Oncotype Dx, have paved the way for personalized therapy in the adjuvant setting for hormone receptor–positive cancer, where patients with intermediate risk have no benefits with the addition of chemotherapy to adjuvant endocrine therapy in small node-negative tumors. In the neoadjuvant space, CDK4/6 has established its role as the primary treatment of metastatic hormone receptor–positive breast cancer and is now being tested in the neoadjuvant setting. TNBC has a varied molecular abnormality, and with the incorporation of BRCA 1 and 2 gene testing, patients who were BRCA 1/2 positive and HER2 negative received a PARP inhibitor olaparib, which showed a significant improvement in invasive disease-free survival.
