Effect of Zoledronic Acid Treatment on Bone-related Events in Breast Cancer Patients With Bone Metastases: a Prospective, Multicenter, Real-world Study

Study Overview
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Brief Summary
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non-intervention、real world study； Effect of timing and regular treatment of zoledronic acid on the incidence of SREs in breast cancer patients

Detailed Description
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(1) Main Purpose: To observe the clinical efficacy of zoledronic acid regularly in the prevention of SREs in breast cancer patients with bone metastasis (2) Secondary Objectives: To observe whether zoledronic acid prolonged the time of first SREs in patients with bone metastasis; The clinical efficacy and influencing factors of zoledronic acid in different subgroups were observed by subgroup analysis of population baseline, clinical characteristics (such as different types of breast cancer), past history and complications. To observe the clinical distribution, characteristics, timing and compliance of zoledronic acid administration in Chinese breast cancer patients with first bone metastasis.

Official Title
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Effect of Zoledronic Acid Treatment on Bone-related Events in Breast Cancer Patients With Bone Metastases: a Prospective, Multicenter, Real-world Study

Conditions
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Histologically Confirmed Breast Cancer ,Diagnosis of Bone Metastasis

Intervention / Treatment
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* Other: Non-intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Age ≥18 years 2. Histologically confirmed breast cancer 3. Initial diagnosis of bone metastasis by MRI or CT and treatment with zoledronic acid 4. Serum creatinine ≤265mol/L or 3.0mg/dl 5. CrCl ≥ 30 ml/min 6. Serum Ca2+ concentration 2.0-3.0 mmonl/L 7.ECOG score ≤2 Voluntary research, informed consent Exclusion Criteria: 1. Pregnant and lactating women 2. Severe liver insufficiency (ALT and/or AST higher than 3 times the upper limit of normal) 3. Patients with osteoarthritis or other bone related diseases need bone targeted therapy 4. Patients with uncontrolled dental problems or planned jaw surgery

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| patients in breast cancer with bone metastasis<br>patients in breast cancer with bone metastasis | Other: Non-intervention<br>* Non-intervention,with real world study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| SREs | skeletal-related events (SREs) including pathologic fracture, spinal cord compression, hypercalcemia of malignancy, and the need for radiotherapy and/or surgery to bone | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| time to first on-study SRE | time to first on-study SRE defined as pathologic fracture, radiation or surgery to bone, or spinal cord compression | 3 years |