Table 1.
Main Minimal Residual Disease assessment studies for circulating tumor DNA in colorectal cancers.
| Reference | Type of Study | Tumor Location | Stage (TNM) |
MRD Assessment Method | Number of Pts with ctDNA + after Surgery (%) | RFS/DFS after Surgery |
HR for Relapse; p-value |
% of pts Who Underwent ACT | Number of pts with ctDNA + after ACT (%) | RFS/DFS after ACT |
HR for Relapse; p-Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Tie et al. [102] | Prospective | Colon | II | PCR (Safe-SeqS) | Patients not treated by ACT: 14/178 (7.9%) |
3 years RFS in patients not treated by ACT: in ctDNA –: 90% in ctDNA +: 0% |
HR = 18; p < 0.001 | 23% | 6/52 (11%) | NA | HR = 11; p = 0.001 |
| Tie et al. [103] | Prospective | Colon | III | PCR (Safe-SeqS) | 20/96 (21%) | 3 years RFS: in ctDNA –: 76% in ctDNA +: 47% |
HR = 3.8; p < 0.001 | 100% | 15/88 (17%) | 3 years RFS: in ctDNA-: 87% in ctDNA +: 33% |
HR = 6.8; p < 0.001 |
| Tarazona et al. [104] | Prospective | Colorectal | I-III | Personalized ddPCR | 14/152 (9.2%) | NA | HR = 16.53; p < 0.001 | NA | 7/25 (28%) | NA | HR = 10.02; p < 0.0001 |
| Taieb et al. [105] | Prospective | Colon | II-III | ddPCR | 140/1017 (13.8%) | 3 years DFS: in ctDNA –: 77% in ctDNA+: 66% |
HR = 1.55; p = 0.015 | 100% | NA | NA | NA |
| Tie et al. [106] | Prospective | Rectum | Locally advanced T3/T4 and or N+ | PCR (Safe-SeqS) | 19/159 (11.9%) | 3 years RFS: in ctDNA –: 87 % in ctDNA +: 33% |
HR = 13; p < 0.001 | 64% | NA | NA | NA |
| Loupakis et al. [107] | Prospective | Colorectal | IV (Oligometastatic) | Personalized and tumor informed multiplex PCR (Signatera) |
52/100 (52%) | NA | HR = 4.6; p <0.001 | 38% | NA | NA | NA |
ACT: adjuvant chemotherapy; CI: Confidence interval; CT: chemotherapy; ctDNA: circulating tumor DNA; ddPCR: digital droplet PCR; DFS: Disease free survival; HR: hazard ratio; MRD: Minimal residual disease; PCR: polymerase chain reaction; pts: patients; NA: Not available; NGS: New generation sequencing; NR: Not reached; RFS: Recurrence free survival.