Treatment Response Monitoring Using a Tumor-Informed Circulating Tumor DNA Test in an Advanced Triple-Negative Breast...

Area of Science:

• Oncology
• Genomics
• Molecular Diagnostics

Background:

• Triple-negative breast cancer (TNBC) is an aggressive subtype with limited targeted treatment options.
• Identifying predictive biomarkers for therapy selection and monitoring remains a clinical challenge.
• Current treatment strategies often face resistance, necessitating novel approaches.

Observation:

• A case study involving a patient with highly aggressive, treatment-resistant TNBC was analyzed.
• Comprehensive genomic profiling (CGP) was utilized to identify actionable therapeutic targets.
• Longitudinal circulating tumor DNA (ctDNA) testing was implemented for treatment monitoring.

Findings:

• A tumor-naïve next-generation sequencing panel facilitated therapy selection.
• Personalized, tumor-informed ctDNA assays detected molecular residual disease post-surgery.
• Rising ctDNA levels guided switching between four lines of therapy, demonstrating dynamic treatment adaptation.
• The integrated CGP and ctDNA approach revealed potential for prolonged survival.

Implications:

• This case highlights the utility of combining CGP with longitudinal ctDNA monitoring in TNBC management.
• Biomarker-driven therapeutic selection and dynamic monitoring may improve outcomes in aggressive cancers.
• Such integrated strategies offer a personalized approach to overcome treatment resistance in TNBC.