Breast cancer therapy and bone

Breast cancer is the most common cancer in women and the leading cause of cancer-associated mortality. The estrogen deprivation associated with therapies used to treat this disease may result in significant loss of bone density and a consequent increase in fracture risk. Anti-resorptive osteoporosis therapies (bisphosphonates and the inhibitor of receptor activator of nuclear factor-κB ligand [RANKL] denosumab) play an important role in the mitigation of cancer therapy-induced bone loss (CTIBL), and may function as adjuvant therapy in moderate to high-risk breast cancer to prevent disease recurrence. Various international guidelines have delineated treatment thresholds based on both bone density assessment and clinical risk factors for CTIBL. The role of these bone-targeted therapies as adjuvant anti-cancer treatment is evolving. Currently, evidence supports the use of the bisphosphonates, zoledronic acid and clodronate, in this setting. Unfortunately, a focus on bone health in women with breast cancer is often not prioritized, leaving this group vulnerable to significant bone loss and subsequent fracture.