The therapeutic landscape of human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (mBC) has evolved considerably with the introduction of newer targeted agents such as poly-ADP ribose polymerase inhibitors (PARPi), novel chemotherapeutic agents, immunotherapy, and endocrine therapies. In this scenario, optimizing the appropriate treatment sequence is a daunting task for clinicians. To develop evidence-based answers to key clinical questions on treatment selection and appropriate treatment sequence for the management of patients with HER2- mBC in the era of PARPi, a breast cancer expert group meeting was convened. The expert panel comprised of eight key opinion leaders from Argentina, Brazil, Colombia, Egypt, Mexico, Moscow, South Korea, and the United Arab Emirates, who convened and reviewed the literature, discussed the clinical practices across the participating regions, and formulated answers to key clinical questions for optimizing the management of HER2- mBC. In this review, evidence-based answers have been provided pertaining to (I) the specific mBC population to be considered for BRCA testing, optimal time point of BRCA testing, and genetic counselling in mBC patients; (II) the role of PARPi versus platinum therapy in HER2- mBC patients in the metastatic setting; (III) sequencing treatment in metastatic triple-negative breast cancer (TNBC) and hormone receptor-positive HER2- mBC patients, and defining the place of PARPi in the sequencing algorithms; and (IV) the need for a breast cancer registry for patients with HER2- mBC. This expert review will serve as a comprehensive guide to clinicians for optimizing BRCA testing and managing patients with BRCA mutation (BRCAm) and HER2- mBC. The data collected from the proposed HER2- mBC registry will help understand the treatment practices, identify unmet needs, and develop strategic policies regionally to help improve access to optimized care of HER2- mBC.
Keywords: BRCA mutations; Human epidermal growth factor receptor; breast cancer; immunotherapy; poly-ADP ribose polymerase inhibitors (PARPi).