Table 1 Clinical and conventional MRI characteristics of children with MB
Characteristics | Training cohort (n = 60) | p value | Internal validation cohort (n = 24) | p value | External validation cohort (n = 40) | p value | |||
|---|---|---|---|---|---|---|---|---|---|
Non-metastasis (n = 38, %) | Metastasis (n = 22, %) | Non-metastasis (n = 15, %) | Metastasis (n= 9, %) | Non-metastasis (n =27, %) | Metastasis (n= 13, %) | ||||
Age (mean ± SD, years) | 6.2 ± 3.5 | 4.3 ± 2.5- | 0.028 | 5.1 ±2.9 | 3.6 ±1.7 | 0.154 | 6.3 ±3.4 | 6.4 ±3.3 | 0.937 |
Gender (%) | Â | Â | 1.000 | Â | Â | 0.597 | Â | Â | 0.360 |
 Male | 26 (68.4) | 15 (68.2) |  | 7 (46.7) | 6 (66.7) |  | 13 (48.1) | 9 (69.2) |  |
 Female | 12 (31.6) | 7 (31.8) |  | 8 (53.3) | 3 (33.3) |  | 14 (51.9) | 4 (30.8) |  |
Histopathologic subtype (%) | Â | Â | 0.632 | Â | Â | 0.444 | Â | Â | 0.748 |
 Classic | 33 (86.8) | 17 (77.3) |  | 10 (66.7) | 8 (88.9) |  | 21 (77.8) | 11 (84.6) |  |
 Large cell/anaplastic | 1 (2.6) | 1 (4.5) |  | 4 (26.7) | 1 (11.1) |  | 1 (3.7) | 0 (0) |  |
 Desmoplastic-nodule | 4 (10.5) | 4 (18.2) |  | 1 (6.7) | 0 (0.0) |  | 5 (18.5) | 2 (15.4) |  |
Location (%) | Â | Â | 1.0000 | Â | Â | 0.507 | Â | Â | 1 |
 Midline | 34 (89.5) | 20 (90.9) |  | 15 (100.0) | 9 (100.0) |  | 24 (88.9) | 11 (84.6) |  |
 Nonmidline | 4 (10.5) | 2 (9.1) |  | 0 (0.0) | 0 (0.0) |  | 3 (11.1) | 2 (15.4) |  |
Enhancement pattern (%) | Â | Â | 0.4032 | Â | Â | 0.052 | Â | Â | 0.399 |
 Diffuse | 23 (60.5) | 17 (77.3) |  | 8 (53.3) | 9 (100.0) |  | 17 (63.0) | 10 (76.9) |  |
 Incomplete | 10 (26.3) | 3 (13.6) |  | 4 (26.7) | 0 (0.0) |  | 3 (11.1) | 2 (15.4) |  |
 Minimal | 5 (13.2) | 2 (9.1) |  | 3 (20.0) | 0 (0.0) |  | 7 (25.9) | 1 (7.7) |  |
Necrosis or cyst(%) | Â | Â | 0.8664 | Â | Â | 0.729 | Â | Â | 0.311 |
 None | 5 (13.2) | 2 (9.1) |  | 1 (6.7) | 0 (0.0) |  | 0 (0) | 1 (7.7) |  |
 Small | 22 (57.9) | 14 (63.6) |  | 8 (53.3) | 5 (55.6) |  | 22 (81.5) | 9 (69.2) |  |
 Both | 11 (28.9) | 6 (27.3) |  | 6 (40.0) | 4 (44.4) |  | 5 (18.5) | 3 (23.1) |  |
minADC (mean ± SD) mm2/s) | 0.4 ± 0.1 | 0.4 ± 0.1 | 0.191 | 0.5 ± 0.1 | 0.4 ± 0.1 | 0.0212 | 0.5 ± 0.1 | 0.4 ± 0.1 | 0.171 |