Safety and Efficacy of Long-Term Zoledronic Acid in Advanced Breast Cancer with Bone Metastasis in South China

Figure 4

Forest plot depicting the hazard ratios of different subgroups in group A (ZA 6–24 months) and group B (ZA > 24 months). The square data point represents the hazard ratio, and the endpoints represent 95% confidence intervals. The hazard ratio and value were calculated by the Cox regression test. a: Load-bearing bones consist of the spine, pelvis, and the limbs; these are strongly influenced by muscle strength, which affects the healing of fractures, bone grafts, osteotomies, and arthrodesis. The remainder are non-load-bearing bones, such as the skull, rib, clavicle, humerus, and ulna. b: Nonvisceral organ metastasis includes bone, lymph node, soft tissue, chest wall, and ipsilateral breast cancer.