CTCs in metastatic breast cancer

Area of Science:

• Oncology
• Biomarkers
• Translational Research

Background:

• Circulating tumor cells (CTCs) are validated prognostic markers in metastatic breast cancer (MBC).
• A basal CTC count of ≥5 cells/7.5 mL blood indicates a poor prognosis in MBC patients.
• Current prognostic assessments rely on standard radiological evaluations.

Purpose of the Study:

• To highlight the prognostic value of CTC enumeration in MBC.
• To emphasize the potential of CTCs for early disease progression prediction.
• To explore the utility of CTC molecular characterization for identifying novel therapeutic targets.

Main Methods:

• Enumeration of CTCs using the FDA-cleared CellSearch® system.
• Monitoring CTC counts during treatment for early progression detection.
• Molecular characterization of CTCs, including receptor expression analysis (e.g., AdnaTest BreastCancerSelect™).

Main Results:

• CTC enumeration serves as an independent prognostic factor for progression-free survival (PFS) and overall survival (OS) in MBC.
• CTC counts can predict disease progression earlier than conventional radiological methods.
• Significant discordance in receptor expression between primary tumors and CTCs has been observed.

Conclusions:

• CTC enumeration is a valuable tool for monitoring MBC progression and guiding treatment decisions.
• CTCs offer a "liquid biopsy" approach for real-time tumor characterization.
• Molecular profiling of CTCs holds promise for discovering new druggable targets in metastatic breast cancer.