TABLE 2.
Comparisons of Imaging Features in Training and Validation Cohort
| Imaging Features | Training Cohort (n = 77) | Validation Cohort (n = 33) | ||||
|---|---|---|---|---|---|---|
| Low Ki67 Group (n = 27) | High Ki67 Group (n = 50) | P | Low Ki67 Group (n = 11) | High Ki67 Group (n = 22) | P | |
| Maximum length, median (IQR), cm | 3.5 (2.3–5.0) | 4.3 (2.3–7.2) | 0.337 | 2.5 (1.2–3.8) | 4.9 (3.6–8.4) | 0.009 |
| No. tumors (%) | 0.377 | 0.681 | ||||
| Solitary | 16 (59.3) | 36 (72.0) | 9 (81.8) | 15 (68.2) | ||
| Multiple | 11 (40.7) | 14 (28.0) | 2 (18.2) | 7 (31.8) | ||
| Tumor margin (%) | 0.049 | 0.036 | ||||
| Smooth | 20 (74.1) | 24 (48.0) | 9 (81.8) | 8 (36.4) | ||
| Nonsmooth | 7 (25.9) | 26 (52.0) | 2 (18.2) | 14 (63.6) | ||
| Peritumoral arterial enhancement (%) | 0.125 | 0.259 | ||||
| Absent | 23 (85.2) | 33 (66.0) | 9 (81.8) | 13 (59.1) | ||
| Present | 4 (14.8) | 17 (34.0) | 2 (18.2) | 9 (40.9) | ||
| Enhancement pattern (%) | 1 | 1 | ||||
| Typical | 26 (96.3) | 47 (94.0) | 10 (90.9) | 21 (95.5) | ||
| Atypical | 1 (3.7) | 3 (6.0) | 1 (9.1) | 1 (4.5) | ||
| Tumor hypointensity on HBP (%) | 1 | 1 | ||||
| Present | 25 (92.6) | 47 (94.0) | 10 (90.9) | 19 (86.4) | ||
| Absent | 2 (7.4) | 3 (6.0) | 1 (9.1) | 3 (13.6) | ||
| Peritumoral hypointensity on HBP (%) | 0.119 | 0.687 | ||||
| Absent | 25 (92.6) | 38 (76.0) | 10 (90.9) | 19 (86.4) | ||
| Present | 2 (7.4) | 12 (24.0) | 1 (9.1) | 3 (13.6) | ||
| Radiologic capsule (%) | 0.948 | 0.121 | ||||
| Present | 22 (81.5) | 39 (78.0) | 6 (54.5) | 18 (81.8) | ||
| Absent | 5 (18.5) | 11 (22.0) | 5 (45.5) | 4 (18.2) | ||
| SITumor (b = 800 s/mm2) | 124.8 (13.8) | 188.7 (16.2) | 0.014 | 122.8 (47.8) | 168.4 (95.6) | 0.148 |
| SIBackground (b = 800 s/mm2) | 6.1 (0.6) | 6.4 (0.4) | 0.439 | 7.0 (0.8) | 6.1 (0.7) | 0.259 |
| SILiver (b = 800 s/mm2) | 55.0 (6.6) | 67.7 (6.2) | 0.219 | 54.4 (21.0) | 54.7 (32.5) | 0.975 |
| ADCTumor (×10−3 mm2/s) | 1075.7 (55.1) | 1003.4 (35.1) | 0.127 | 1146.4 (78.4) | 1045.1 (51.3) | 0.237 |
| SNR | 44.9 (6.0) | 67.9 (5.8) | 0.014 | 44.2 (17.2) | 60.6 (34.4) | 0.148 |
| Contrast | 2.5 (0.2) | 3.1 (0.2) | 0.121 | 2.6 (0.4) | 3.5 (0.4) | 0.079 |
P-values are statistically significant in boldface format.