[Circulating tumor cells: a new challenge for laboratory medicine]

Area of Science:

• Oncology
• Molecular Biology
• Cancer Research

Context:

• Circulating tumor cells (CTCs) are found in the blood of patients with most adenocarcinomas.
• Their release involves epithelial-mesenchymal transition, and their metastatic potential is debated due to heterogeneous phenotypes.
• CTCs can differ from primary tumors, particularly in drug resistance markers like HER2 and hormone receptors.

Purpose:

• To review the current understanding and clinical utility of circulating tumor cells (CTCs) in cancer management.
• To highlight the discrepancies between CTCs and primary tumors regarding therapeutic targets.
• To discuss the limitations of current CTC detection methods and the need for standardization.

Summary:

• CTCs are epithelial cells shed from tumors, detectable in various cancers.
• Their heterogeneity and molecular differences from primary tumors impact treatment sensitivity.
• The CellSearch system is FDA-approved for specific cancers, demonstrating CTCs' prognostic and predictive value.
• Further studies are required to validate CTCs for optimizing therapy selection, real-time monitoring, and as surrogate endpoints.

Impact:

• Standardized CTC analysis could revolutionize cancer treatment by enabling personalized therapy selection and real-time monitoring of drug efficacy.
• CTCs may serve as a non-invasive biomarker for predicting treatment outcomes and evaluating novel therapeutic strategies.
• Investigating CTC biological features beyond enumeration is crucial for advancing their clinical application.