Table 5.
Clinical relevance of ctDNA clearance at each stage of treatment.
| Study Design | Sample Size | Study Population | ctDNA Detection Method | Timepoint of ctDNA Sampling | ctDNA Clearance Rate | Outcome | |
|---|---|---|---|---|---|---|---|
| After surgery | Prospective, multi-center cohort study [51] |
49 | Stage II CRC Stage III CRC |
Droplet Digital PCR | Day 5 after surgery | 75% | Recurrence rate ctDNA+: 44.4% ctDNA−: 13.7% |
| Prospective, multi-center study [56] | 240 | Stage II CRC Stage III CRC |
NGS | Days 3–7 after surgery | 92% | 2-year RFS: ctDNA+: 39.3% ctDNA−: 89.4% |
|
| Prospective, multi-center cohort study [8] |
94 | Stage I CRC Stage II CRC Stage III CRC |
Multiplex PCR-based NGS | Day 30 after surgery | 89% | Recurrence rate: ctDNA+: 70% ctDNA−: 11.9% |
|
| After adjuvant chemotherapy | Prospective, multi-center cohort study [8] |
10 | Stage I CRC Stage II CRC Stage III CRC |
Multiplex PCR-based NGS | After completion of chemotherapy | 30% | NM |
| Prospective cohort study [64] |
6 | Stage II CC | Safe-SeqS | After completion of chemotherapy | 50% | 2-year RFS: ctDNA+: 27% ctDNA−: 82% |
|
| Multi-center, cohort study [50] |
95 | Stage III CC | Safe-SeqS | After completion of chemotherapy | 68% | 3-year RFI: ctDNA+: 30% ctDNA−: 77% |
CC: colon cancer, Safe-SeqS: Safe-Sequencing System, RFS: Regression-Free Survival, NM: Not Mentioned, and RFI: Regression-Free Interval.