Impact of Intensive Follow-up for Bone Metastasis on Characteristics and Prognosis of Chinese Breast Cancer Patients

Study Overview
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Brief Summary
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The purpose of this study is to retrospectively collect and analyse the characteristics of breast cancer patients with bone metastasis, and compare the impact of intensive follow-up with standard post-operative surveillance on survival of Chinese breast cancer patients.

Detailed Description
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Breast cancer is one of the most common malignant tumors in women, and the incidence rate is gradually increasing, accounts for the first place in the incidence of female malignant tumors. Bone metastasis is the most common distant metastatic site for breast cancer, accounting for approximately 70% of all patients with advanced breast cancer. About 26%-50% of breast cancer patients with primary metastases are bone. Autopsy results showed that the overall incidence of breast cancer bone metastasis was about 47%-85%. Postoperative routine screening for bone metastases in breast cancer patients, whether domestic or foreign, is not recommended in most guidelines. These recommendations were based on two prospective randomized controlled trials in Italy in 1990s, indicated that a bone scan every six months or annually didn't provide a survival benefit to the patient. However, there were researches showing that about 11% of patients with asymptomatic breast cancer have bone metastases, suggesting that early screening might detect more patients with asymptomatic bone metastases. The meta-analysis also pointed out that early screening may prolong the disease-free survival of patients. Besides, the imaging techniques have advance rapidly and remarkably since then. New trials are needed to figure out whether imaging screening of asymptomatic patients should be routinely performed to detect more asymptomatic bone metastases needs further investigation.

Official Title
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Impact of Intensive Follow-up for Bone Metastasis on Characteristics and Prognosis of Chinese Breast Cancer Patients: A Multicenter Retrospective Study

Conditions
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Breast Cancer, Bone Metastases

Intervention / Treatment
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* Diagnostic Test: Intensive screening / routine screening


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: A. Histologically proven breast cancer confirmed by biopsy or pathological examination of the resected tumor. B. Histologically confirmed breast cancer patients, fulfilling any of the following: . Multiple bone metastases indicated by bone scan . Bone scan positive, and proven by other imaging examinations, including computed tomography (CT), magnetic resonance imaging (MRI) and X-ray. . Bone scan positive, with clinical symptoms, including bone pain, pathologic fracture, spinal cord compression and so on. . Bone metastases indicated by PET-CT . Histologically proven bone metastases Exclusion Criteria: A. No bone metastases confirmed by pathological examination B. Bone metastases secondary to other malignant tumor other than breast cancer C. Secondary primary tumor

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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Female

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Bone metastasis screening<br>The information about bone metastasis screening is retrospectively collected. | Diagnostic Test: Intensive screening / routine screening<br>* Recommendation and results of bone imaging such as bone scan or PET/CT, or bone CT /MR are collected.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival | defined as the period from randomization to death from any cause, and it is censored at the last follow-up date when the patient is alive | 60 months, and bone scan is repeated every 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| disease-free survival | defined as time to disease recurrence (invasive local, regional, or distant metastasis) or death from any cause | 60 months, and bone scan is repeated every 12 months | 
| distant metastasis-free survival | defined as time to distant metastasis | 60 months, and bone scan is repeated every 12 months |