Circulating tumors cells as biomarkers: progress toward biomarker qualification

Area of Science:

• Oncology
• Biomarker Discovery
• Molecular Diagnostics

Background:

• Personalized cancer medicine relies on tumor-specific biomarkers for targeted therapy selection and response assessment.
• Circulating tumor cells (CTCs) detection correlates with inferior prognosis, while their reduction post-treatment indicates improved outcomes.
• Advances enable CTC evaluation from routine blood samples, addressing needs in cancer diagnosis and treatment monitoring.

Purpose of the Study:

• To outline the necessary steps for developing and validating circulating tumor cell (CTC) biomarker assays.
• To qualify specific CTC tests for clinical decision-making in practice and drug development.
• To highlight the potential of point-of-care CTC testing.

Main Methods:

• Review of current technological advances in CTC detection, isolation, capture, and characterization.
• Analysis of the process for developing and analytically validating CTC biomarker assays.
• Examination of the evidence required for biomarker use in clinical decision-making.

Main Results:

• Multiple assays for CTC biomarkers are under development, with no single definition or biomarker.
• Analytical validation is essential before any CTC biomarker assay can be used for medical decisions.
• The process requires rigorous testing to generate supporting evidence for clinical application.

Conclusions:

• Validated CTC biomarker assays are critical for advancing personalized cancer medicine.
• Standardized development and validation pathways are needed to ensure reliable CTC tests.
• Successful qualification of CTC assays will impact clinical practice and drug development, with potential for point-of-care applications.