Table 1.
Clinical characteristics and radiomics scores for the perineural invasion in the training and testing datasets.
| Variables | All patients (N = 94) | Training dataset (N = 65) | Testing dataset (N = 29) | P value |
|---|---|---|---|---|
| PNI status | 1 | |||
| Negative | 63 (67.02) | 44 (67.69) | 19 (65.52) | |
| Positive | 31 (32.98) | 21 (32.31) | 10 (34.48) | |
| Age | 59.20 ± 12.43 | 59.37 ± 12.94 | 58.83 ± 11.41 | 0.846 |
| Gender | 0.707 | |||
| Male | 72 (76.60) | 51 (78.46) | 21 (72.41) | |
| Female | 22 (23.40) | 14 (21.54) | 8 (27.59) | |
| CEA level | 0.757 | |||
| ≤ 3.4 ng/ml | 46 (48.94) | 33 (50.77) | 13 (44.83) | |
| > 3.4 ng/ml | 48 (51.06) | 32 (49.23) | 16 (55.17) | |
| CA19-9 level | 1 | |||
| ≤ 22 ng/ml | 78 (82.98) | 54 (83.08) | 24 (82.76) | |
| > 22 ng/ml | 16 (17.02) | 11 (16.92) | 5 (17.24) | |
| Tumor location | 0.916 | |||
| Middle and high | 51 (54.26) | 36 (55.38) | 15 (51.72) | |
| Low | 43 (45.74) | 29 (44.62) | 14 (48.28) | |
| Tumor length (cm) | 5.25 (4.10, 6.78) | 5.60 (4.60, 6.70) | 4.70 (3.40, 7.10) | 0.271 |
| Tumor thickness(cm) | 1.40 (1.10, 1.60) | 1.40 (1.10, 1.60) | 1.40 (1.10, 1.70) | 0.908 |
| R_T staging | 0.466 | |||
| T 1–2 | 23 (24.47) | 14 (21.54) | 9 (31.03) | |
| T 3–4 | 71 (75.53) | 51 (78.46) | 20 (68.97) | |
| R_N staging | 1 | |||
| N0 | 25 (26.60) | 17 (26.15) | 8 (27.59) | |
| N1–2 | 69 (73.40) | 48 (73.85) | 21 (72.41) | |
| P_T staging | 0.443 | |||
| T 1–2 | 32 (34.04) | 20 (30.77) | 12 (41.38) | |
| T 3–4 | 62 (65.96) | 45 (69.23) | 17 (58.62) | |
| R_N staging | 0.864 | |||
| N0 | 45 (47.87) | 32 (49.23) | 13 (44.83) | |
| N1–2 | 49 (52.13) | 33 (50.77) | 16 (55.17) | |
| T2WI score | − 0.79 (− 1.10, − 0.45) | − 0.77 (− 1.09, − 0.39) | − 0.80 (− 1.18, − 0.53) | 0.697 |
| DWI score | − 0.69 (− 0.78, − 0.59) | − 0.69 (− 0.78, − 0.60) | − 0.69 (− 0.76, − 0.59) | 0.990 |
| CT score | − 0.90 (− 1.57, − 0.41) | − 0.79 (− 1.52, − 0.40) | − 1.14 (− 1.93, − 0.76) | 0.099 |
Data are presented as mean ± SD, No. (%) or median (25%, 75%). PNI perineural invasion, CEA carcinoembryonic antigen, CA19-9 cancer antigen 19–9, R_T staging T staging was diagnosed based on rectal MR and CT images, R_N staging N staging was diagnosed based on rectal MR and CT images, P_T staging T staging was diagnosed by pathology, P_N staging N staging was diagnosed by pathology.