Journal: Molecular oncology
This study developed a methylation-specific droplet digital PCR (MS-ddPCR) multiplex assay to detect circulating tumor DNA (ctDNA) in colorectal cancer (CRC) patients using tumor-specific and tissue-conserved methylation markers.
The assay demonstrated:
- High specificity: 96.7%
- Sensitivity in detecting ctDNA: 64.4% in localized CRC and 89.2% in metastatic CRC (mCRC) patients
Importantly, changes in ctDNA levels after the first treatment cycle correlated significantly with progression-free survival (PFS) and overall survival (OS) in mCRC patients.
Patients classified by ctDNA response criteria showed marked differences in outcomes:
- Good responders: notably longer PFS and OS
- Poor responders and those with progressive disease: shorter PFS and OS
This cost-effective and sensitive assay offers a valuable tool for:
- Early treatment response monitoring
- Prognostication
- Guiding personalized therapy in CRC, especially in metastatic cases