Oncologic Outcomes and Toxicities of Salvage Treatment in Patients With Locoregionally Recurrent Breast Cancer

Study Overview
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Brief Summary
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The purpose of this study is to evaluate clinical outcomes and adverse events of salvage treatment for locoregional recurrence of breast cancer. The main questions it aims to answer are: Clinical outcomes after salvage treatment for locoregional recurrence Adverse events and quality of life after salvage treatment for locoregional recurrence Patient characteristics and treatment specifics which are related to the clinical outcomes and/or adverse events Molecular signature associated with treatment resistance Participants will be assessed by multi-dimensional methods during and after radiation therapy: Assessment for the disease status (disease-free or recurrence) including physical and radiologic examination Assessment for the adverse events according to CTCAE version 5.0 Assessment for the molecular signature using residual tissue after pathologic diagnosis Assessment for the quality of life using questionnaires (BREAST-Q)

Official Title
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A Prospective Registry Study to Evaluate Oncologic Outcomes and Toxicities of Salvage Treatment in Patients With Locoregionally Recurrent Breast Cancer

Conditions
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Breast Cancer

Intervention / Treatment
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* Other: Salvage treatment (surgery and/or radiation therapy)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female patients with age 18 to 100. Previous standard definitive treatment for initial breast cancer Locoregional recurrence without distant metastasis Planned salvage treatment for locoregional recurrence Informed consent of the participant Exclusion Criteria: - Not anticipated for complying the study protocol

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Salvage treatment after locoregional recurrence<br>Participants who previously completed standard treatment for breast cancer and experienced locoregional recurrence alone will be undergo salvage treatment including surgery and/or radiation therapy. | Other: Salvage treatment (surgery and/or radiation therapy)<br>* Appropriate salvage treatment (surgery and/or radiation therapy) will be selected by the treating clinicians considering the disease status.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression-free survival | The event for progression-free survival was defined as any disease progression or breast cancer-related death. | 5 years from the initiation of the salvage therapy | 
| Rate of adverse events | Adverse events related to the salvage therapy will be reported and incidence rate will be calculated. | 5 years from the initiation of the salvage therapy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Locoregional failure rate | The event for locoregional failure rate was defined as recurrence in breast / chest wall or regional lymph node area. | 5 years from the initiation of the salvage therapy | 
| Cancer-specific survival | The event for cancer-specific survival was defined as death of the participant related to the breast cancer. | 5 years from the initiation of the salvage therapy | 
| Quality of life (BREAST-Q) | Quality of life of the participants will be evaluated according to the BREAST-Q™ questionnaires. Higher Q-Score indicates better quality of life. | 5 years from the initiation of the salvage therapy | 
| Breast cosmesis | Cosmesis of the breast will be evaluated according to Harvard/National Surgical Adjuvant Breast and Bowel Project (NSABP)/Radiation Therapy Oncology Group (RTOG) Breast Cosmesis grading scale. This is a 4-point scale (Excellent, Good, Fair, and Poor), and evaluated by the clinicians. | 5 years from the initiation of the salvage therapy |