Adjuvant therapy of HER2⁺ breast cancer

Adjuvant therapy of HER2⁺ breast cancer has evolved dramatically over the past 4 years. It is now widely appreciated that treatment with trastuzumab, when administered concurrently or sequentially with chemotherapy, will decrease the risk of disease recurrence by approximately 50%. Clinical trials have also demonstrated a modest improvement in overall survival, and it is anticipated that this survival advantage will increase with further follow-up. Nevertheless, there are patients who will experience disease recurrence in spite of optimal trastuzumab-based therapy, and new treatment approaches are needed for these individuals. The results of the initial randomized trials have also given rise to a number of difficult questions that clinicians and patients face on a daily basis. The presentation will focus on controversial topics in the adjuvant treatment of HER2⁺ disease, including: the treatment of small, node-negative tumors; the uncertainty surrounding intermediate HER2⁺ test results; and the concerns about cardiac toxicity. New treatment approaches for HER2⁺ breast cancer that hold promise for the adjuvant setting will also be discussed.