Clinical utility of longitudinal circulating tumor DNA analysis in metastatic colorectal cancer patients receiving palliative chemotherapy.
Summary
This prospective observational study assessed the utility of circulating tumor DNA (ctDNA) for mutational profiling and dynamic monitoring in 33 patients with metastatic colorectal cancer receiving palliative chemotherapy. ctDNA was detected in most patients at baseline, revealing frequent mutations in APC, TP53, KRAS, and PIK3CA. Good concordance was observed between plasma ctDNA profiles and tissue data. Longitudinal analysis showed the emergence of acquired mutations, particularly RAS mutations under anti-EGFR therapy, and correlated high ctDNA levels with shorter overall survival. These findings highlight ctDNA's potential to guide personalized treatment strategies and monitor resistance.
Analysis
🔴 CLINIQUE: This prospective observational study demonstrates the clinical utility of ctDNA as a prognostic and potentially predictive biomarker in metastatic colorectal cancer. The correlation between elevated ctDNA levels and shorter overall survival suggests its role in prognostic assessment. The ability to detect acquired resistance mutations, such as RAS mutations under anti-EGFR therapy, could justify clinical trials to adapt treatments in real-time, enabling personalized therapeutic strategies and resistance monitoring. Clinical impact could be seen in the medium term (3-5 years) with further validation studies. 🟢 BIOMOL: The study validates the non-invasive approach of plasma ctDNA analysis for comprehensive genomic profiling, showing high concordance (86.9%) with tissue NGS data. It highlights the discovery of resistance mechanisms, particularly the emergence of new RAS mutations (specifically Q61 variants) under anti-EGFR therapy, and a broader range of alterations under anti-VEGF therapy. The technology used is ctDNA analysis, which allows for tracking dynamic changes in mutational profiles, offering analytical validity for variant detection and monitoring their allele frequency. The use of liquid biopsies (plasma) is a major advantage for longitudinal monitoring.