Choosing the appropriate pharmacotherapy for breast cancer during pregnancy: what needs to be considered?

Introduction: Breast cancer is the most commonly diagnosed malignancy during pregnancy. Breast cancer during pregnancy is a challenging clinical condition requiring proper and timely multidisciplinary management. Areas covered: This review focuses on the management of breast cancer during pregnancy with a focus about the current state-of-the-art on the feasibility and safety of pharmacotherapy approaches in this setting. Expert opinion: Multidisciplinary care is key for a proper diagnostic-therapeutic management of breast cancer during pregnancy. Engaging patients and their caregivers in the decision-making process is essential and psychological support should be provided. The treatment of patients with breast cancer during pregnancy should follow the same recommendations as those for breast cancer in young women outside pregnancy but taking into account the gestational age at the time of treatment.Anthracycline-, cyclophosphamide-, and taxane-based regimens can be safely administered during the second and third trimesters with standard protocols, preferring weekly regimens whenever possible. Endocrine therapy, immune checkpoint inhibitors, and targeted agents are contraindicated throughout pregnancy, also due to the very limited data available to guide their administration in this setting. During treatment, careful fetal growth monitoring is mandatory, and even after delivery proper health monitoring for the children exposed in utero to chemotherapy should be continued.