Colorectal Cancer CTCs Detection Using Two FCM Protocol Approaches

Area of Science:

• Oncology
• Biotechnology
• Medical Diagnostics

Background:

• Circulating tumor cells (CTCs) are crucial biomarkers for personalized cancer therapy and therapeutic target discovery.
• Current CTC identification methods like CellSearch® and Amnis® are effective but can be complex and costly.
• Developing accessible methods for CTC detection is essential for broader clinical application.

Purpose of the Study:

• To establish and evaluate two cost-effective flow cytometry (FCM) protocols for identifying and enumerating CTCs in colorectal cancer (CRC) patients.
• To compare the efficacy of these novel FCM protocols against existing methods.
• To assess the correlation of CTC counts with clinical parameters in CRC.

Main Methods:

• Two distinct FCM protocols (direct and intracellular) were developed and validated using immunomagnetic enrichment.
• CTC enumeration was performed on blood samples from CRC patients before and after surgery.
• Blood from healthy donors served as a negative control, and the Cyflow® Space cytometer was utilized.

Main Results:

• Both FCM protocols successfully detected and enumerated CTCs in CRC patients, showing a statistically significant increase in CTC numbers within the patient group (p < 0.05).
• The intracellular protocol demonstrated higher sensitivity (62.7%) and specificity (70%) compared to the direct protocol (49.2% SN, 58.3% SP).
• Significant correlations were observed between intracellular CTC counts and adenocarcinoma, lymph node infiltration, and disease stage (p < 0.05).

Conclusions:

• Two novel, low-cost FCM protocols for CTC detection in colorectal cancer were successfully established.
• These methods provide a viable alternative for CTC enumeration, potentially improving accessibility in clinical settings.
• While CTC numbers increased significantly in patients, no significant difference was found before and after surgery, warranting further investigation.