Assessment of the benefits of bone modifying agents in the management of advanced breast, prostate, and lung cancers

Purpose of review Skeletal metastases occur in approximately 80% of advanced breast, 70% of advanced prostate, and 30% of lung cancers, and place patients at increased risk of skeletal related events (SRE). Bone modifying agents (BMAs) have been shown to prevent or delay SRE development. Our objective was to summarize the role of these agents in the management of these three cancers. Recent findings Total 52 studies met our inclusion criteria. These highlighted the benefit of BMAs in reducing SREs in metastatic breast and castrate resistant prostate cancer (mCRPC), with less clear impact on reducing SRE in lung cancer, or on improving progression-free and overall survival due to significant heterogeneity in trial design and outcomes. Benefits in SRE reduction occurred with bisphosphonates and denosumab, however when compared, denosumab was superior. Denosumab however is not more cost effective, and multiple trials support potential de-escalation to either 12 weekly dosing or other reduced duration. Summary There is a large body of evidence to support the role of BMAs in reducing SREs in metastatic breast and mCRPC. Impact on survival outcomes is heterogeneous, and future large database trials would be helpful in identifying which subgroups of patients truly have survival benefit from BMAs.