Targeted therapy for breast cancer in older patients

Older patients are one of the most relevant sub-groups of patients with breast cancer and will only gain in importance as demographic transition unfolds. Their management, in both the early and advanced settings, should take into consideration specific clinical needs and is made more difficult by the limited availability of evidence on the efficacy and safety of standard treatment regimens in older patients. At the root of this situation is the low rate of participation of older patients in clinical trials, often due to age limits for inclusion, and limitations on the participation of persons with significant comorbidities or organ dysfunction. Although this has begun to change in recent years, most agents currently in use have not been tested in a substantial number of older patients. This includes the targeted agents that have, in the last fifteen years, changed the prognosis of patients with early and advanced breast cancer. Most data guiding the use of targeted agents in older patients come from sub-analysis of larger trials or small retrospective cohort studies. The goal of this review is to go over the available evidence regarding the efficacy and safety of targeted agents approved for use in breast cancer (trastuzumab, lapatinib, T-DM1, pertuzumab, neratinib, palbociclib, bevacizumab, ribociclib, abemaciclib, everolimus, olaparib, talazoparib), and place their side effects into an older-specific context in order to help medical oncologists when making treatment decisions and managing older patients with breast cancer.