Table 1.
Main characteristics of stage II CRC resected patients included in the study.
| Characteristics | Recurrent patients | Nonrecurrent patients | P value | Positive ctDNA | Negative ctDNA | P value | |
|---|---|---|---|---|---|---|---|
| Total | 54 | 57 | 10 | 101 | |||
| Age | Mean age (years) | 66.1 | 65.9 | 71.5 | 65.4 | ||
| Range | 38.7 - 85.9 | 43.3 - 81.3 | 56.6 - 84.3 | 38.7 - 85.8 | |||
| <60 years | 14 (25.9%) | 9 (15.8%) | 0.35 | 2 (20.0%) | 21 (20.8%) | 0.04 a | |
| 60-69 years | 19 (35.2%) | 26 (45.6%) | 1 (10.0%) | 44 (43.6%) | |||
| ≥70 years | 21 (38.9%) | 22 (38.6%) | 7 (70.0%) | 36 (35.6%) | |||
| Sex* | Female | 21 (38.9%) | 21 (36.8%) | 0.82 | 4 (40.0%) | 38 (37.6%) | 1 b |
| Male | 33 (61.1%) | 36 (63.2%) | 6 (60.0%) | 63 (62.4%) | |||
| Tumor location* | Right-sided | 20 (37.0%) | 23 (40.4%) | 0.91 | 5 (50.0%) | 38 (37.6%) | 0.91a |
| Left-sided | 21 (38.9%) | 22 (38.6%) | 3 (30.0%) | 40 (39.6%) | |||
| Rectal | 13 (24.1%) | 12 (21%) | 2 (20.0%) | 23 (22.8%) | |||
| Lymph nodes analyzed | <12 | 11(20.4%) | 11 (19.3%) | 0.89 | 3 (30.0%) | 19 (18.8%) | 0.41a |
| ≥12 | 43 (79.6%) | 46 (80.7%) | 7 (70.0%) | 82 (81.2%) | |||
| T stage | T2-3 | 39 (72.2%) | 50 (87.7%) | 0.04 | 8 (80.0%) | 81 (80.2%) | 1a |
| T4 | 15 (27.8%) | 7 (12.3%) | 2 (20.0%) | 20 (19.8%) | |||
| VELIPI criteria | None or unknown | 34 (70.0%) | 40 (70.2%) | 0.42 | 3 (30.0%) | 71 (70.3%) | 1 a |
| One or more | 20 (30.0%) | 17 (29.8%) | 7 (70.0%) | 30 (29.7%) | |||
| Emergency Surgery | No | 37 (68.5%) | 47 (82.5%) | 0.09 | 6 (60.0%) | 78 (77.2%) | 0.25a |
| Occlusion or Perforation | 17 (31.5%) | 10 (17.5%) | 4 (40.0%) | 23 (22.8%) | |||
| Differentiation | Well or moderate | 49 (90.7%) | 50 (87.7%) | 0.61 | 9 (90.0%) | 90 (89.1%) | 1 a |
| Poor or unknown | 5 (9.3%) | 7 (12.3%) | 1 (10.0%) | 11 (10.9%) | |||
| Postoperative CEA | Positive | 1 (1.9%) | 3 (5.3%) | 0.47a | 7 (70.0%) | 94 (93.1%) | 0.047 a |
| Negative | 49 (90.7%) | 52 (91.2%) | 1 (10.0%) | 3 (3.0%) | |||
| Unknown | 4 (7.4%) | 2 (3.5%) | 2 (20.0%) | 4 (3.9%) | |||
| Neoadjuvant CRT* | No | 44 (81.5%) | 52 (91.2%) | 0.13 | 9 (90.0%) | 87 (86.1%) | 1 a |
| Yes | 10 (18.5%) | 5 (8.8%) | 1 (10.0%) | 14 (13.9%) | |||
| Time from surgery to | Median time | 81 | 99 | 0.53 c | 60 | 91 | 0.53 d |
| blood sample collection (days) | Range | 15 - 1,301 | 29 - 1,842 | 19 - 1,301 | 15 - 1,842 | ||
| Adjuvant CT* | No | 32 (59.3%) | 33 (57.9%) | 0.88 | 6 (60.0%) | 59 (58.4%) | 1 b |
| Yes | 22 (40.7%) | 24 (42.1%) | 4 (40.0%) | 42 (41.6%) | |||
| Blood collection after | No | 4 (18.2%) | 6 (25.0%) | 0.84 b | 3 (75.0%) | 7 (16.7%) | 0.03 a |
| beginning of CT*§ | Yes | 18 (81.8%) | 18 (75.0%) | 1 (25.0%) | 35 (83.3%) | ||
| Postoperative ctDNA status | Negative Positive | 45 (83.3%) 9 (16.7%) | 56 (98.2%) 1 (1.8%) | 0.02 b |
*Nonrecurrent patients were initially matched with recurrent patients on these factors. tVELIPI criteria include vascular, lymphatic and/or perineural invasion. §Among patients treated with adjuvant chemotherapy. For p value calculation, Chi-squared test have been used, except if
a
Fisher’s exact test for count data.
b
Pearson’s Chi-squared test with Yate’s continuity correction.
c
Student’s t test or
d
Wilcoxon signed ranks test.
e
Duration was assessed only on the 36 patients that performed a blood collection after the beginning of adjuvant chemotherapy.
Bold values correspond to p values lower than 0.05.