The use of osteoclast inhibitors in metastatic breast cancer

Abstract Introduction: In most patients, metastatic breast cancer (MBC) is incurable. Consequently, the goal in this setting is life prolongation and quality of life improvement, although possible long-term effects of anticancer treatment need to be considered. Bone is the most common site of metastasis in breast cancer and its complex management includes minimizing the risk of skeletal-related events (SRE), maximizing pain control, stabilizing or even restoring function, preventing spinal cord compression, hypercalcemia of malignancy and fractures and reducing the need for radiotherapy and orthopedic surgery. Aim: The present paper aims to compare the efficacy and safety of zoledronic acid (and other bisphosphonates) with denosumab in the management of bone metastases in breast cancer patients. Materials and methods: In this article, required information was collected through literature review and keyword query using the PRISMA 2020 guideline. Conclusions: In the metastatic setting, it appears that denosumab is indeed superior to zoledronic acid in delaying and preventing skeletal related events, except for spinal cord compression and risk of surgery, and equally efficient in treatment of already present bone pain and hypercalcemia of malignancy, with similar adverse effects, overall survival and disease progression.