Optimizing Treatment of Stage IV Breast Cancer Through Real-Time Disease Monitoring

Study Overview
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Brief Summary
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This study evaluates if blood tests can detect changes in disease status during treatment for stage IV breast cancer. Information from this study may help researchers learn more about metastatic breast cancer and how to optimize treatment.

Detailed Description
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PRIMARY OBJECTIVES: I. To identify subtype-specific signatures for breast cancer using genomic positioning of plasma deoxyribonucleic acid (DNA) fragments. II. To validate changes in circulating tumor-derived DNA (ctDNA) levels as a biomarker for treatment monitoring in patients with metastatic breast cancer. OUTLINE: Patients undergo collection of blood samples at baseline, 2 weeks after the start of treatment, and at the beginning of each new treatment cycle.

Official Title
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Optimizing Treatment of Metastatic Breast Cancer Through Real-Time Disease Monitoring

Conditions
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Anatomic Stage IV Breast Cancer AJCC v8, Metastatic Breast Carcinoma, Prognostic Stage IV Breast Cancer AJCC v8

Intervention / Treatment
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* Procedure: Biospecimen Collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults > 18 years of age Stage IV breast cancer undergoing cancer treatment Exclusion Criteria: Stage I-III breast cancer Unwilling or unable to give consent Patients with a prior or concurrent malignancy, excluding non-melanoma skin cancers and non-invasive cancers whose natural history or treatment does not have the potential to interfere with the assessment of the investigational marker

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 |
| --- | --- |
| Ancillary-Correlative (biospecimen collection)<br>Patients undergo collection of blood samples at baseline, 2 weeks after the start of treatment, and at the beginning of each new treatment cycle. | Procedure: Biospecimen Collection<br>* Undergo collection of blood samples<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Identification of patients with high circulating tumor-derived deoxyribonucleic acid (ctDNA) fractions (> 50%) | Will analyze across all three subtypes: Estrogen receptor positive (ER+), human epidermal growth factor receptor 2 positive (HER2+), and triple-negative breast cancer (TNBC). Will perform 30x whole genome sequencing (WGS) and generate subtype-specific pooled nucleosome occupancy maps. By comparing these maps with healthy volunteers, we will identify a set of loci across the genome most informative of cancer contribution in cell-free DNA (cfDNA). | Up to 1 year | 
| Detection of treatment failure | Defined as progression of disease on imaging studies. | Up to 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of shallow whole genome sequencing circulating tumor-derived DNA analysis results with available serologic tumor biomarkers used as a standard in clinical practice | shallow whole genome sequencing circulating tumor-derived DNA analysis results with available serologic tumor biomarkers | Up to 1 year |