The Evolving Landscape of HER2-Directed Breast Cancer Therapy.

The management of patients with HER2+ breast cancer has evolved significantly over the preceding decades. HER2 targeting strategies have advanced beyond focusing on the receptor alone to encompass a range of approaches. Current standard of care practices in these patients relies upon dual HER2 blockade with trastuzumab and pertuzumab in the adjuvant and metastatic settings. T-DM1 has proven particularly efficacious in patients with residual disease status post neoadjuvant therapy, with additional therapies approved in the subsequent lines to address recurrent and resistant disease. Advances continue to be made in HER2+ breast cancer with multiple novel agents on the horizon, employing diverse mechanisms of action that are described in this review.