Correlation Between Circulating Tumor Cells and Brain Disease Control After Focal Radiotherapy for Metastases of Breast Cancer

Study Overview
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Brief Summary
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This study assesses the number of CTCs before and 4-5 weeks after focal stereotactic radiotherapy, in single or fractionated dose, and correlate with the local and distant brain progression-free survival in patients with metastatic breast cancer.

Detailed Description
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Brain metastases (BM) are the most prevalent tumors of the central nervous system (CNS), with a ratio of 10: 1 relative to primary tumors. In breast cancer, BM are becoming more frequent due to longer life expectancy. Patients with HER2-positive metastatic disease are prone to develop BM more often and they occur in 20 - 40% of cases. Circulating tumor cells (CTC) originate from the primary tumor and can migrate to distant organs. The possible correlation between CTC and the incidence of brain metastases could help define radiotherapy in patients with oligometastatic or not so widespread disease in the brain. However, there are few studies that evaluate these scenarios. Purpose: To assess the number of CTC before and 4-5 weeks after focal stereotactic radiotherapy in single (SRS) or fractionated (SFRT) dose and correlate with the local and distant brain progression free survival in patients with metastatic breast cancer. Potential invasion markers in these cells will be evaluated and correlated with clinical outcome. Patients and Methods: Prospective, single-center research which will be developed at the Radiation Oncology Department of AC Camargo Cancer Center. Patients with diagnosis of metastatic breast cancer to the brain with an indication of focal radiotherapy, SRS or SFRT, will be recruited. The blood will be collected and processed for analysis of CTC by the ISET method (Rarecells, France). The invasion markers (HER-2, COX-2, EGFR, Notch 1 and ST6GALNAC5) will be analyzed on CTC by immunocytochemistry. Expected Results: If our hypothesis is proven, we may include the analysis and quantification of CTC in clinical practice as early indicator of local or distant recurrence in the brain.

Official Title
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Prospective Evaluation of Correlation Between Circulating Tumor Cells and Brain Disease Control After Focal Stereotactic Radiotherapy for Encephalic Metastases of Breast Cancer

Conditions
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Brain Cancer, Breast Cancer

Intervention / Treatment
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* Diagnostic Test: Circulating tumor cells evaluation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of BM of breast cancer and indication of focal radiotherapy to the brain lesions. Exclusion Criteria: Patients who received WBRT less than 30 days from the initial CTC dosage. Patients who received systemic treatment for less than 7 days of the initial CTC dosage. Pregnant patients.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Circulating Tumor Cells and Radiotherapy<br>Circulating tumor cells evaluation before and 4-5 weeks after focal stereotactic radiotherapy in single (SRS) or fractionated (SFRT) dose and correlate with the local and distant brain progression free survival in patients with metastatic breast cancer | Diagnostic Test: Circulating tumor cells evaluation<br>* Sample collection of circulating tumor cells (CTC) before and 4-5 weeks after focal stereotactic radiotherapy in single (SRS) or fractionated (SFRT) dose.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brain progression-free survival | Local and Distant brain progression | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Circulating Tumor Cells, Stereotactic Radiosurgery