Table 1 The baseline of patients in development and validation cohort
| Â | Development | Â | Â | Validation | Â | Â |
|---|---|---|---|---|---|---|
|  | Benign (n = 57) | Malignant (n = 33) | P | Benign (n = 26) | Malignant (n = 36) | P |
Age, y | 47.0 (40.5–56.0) | 48.0 (35.0–53.5) | 0.58 | 45.0 (32.8–51.8) | 43.5 (35.3–52.5) | 0.87 |
Sex ratio (M: F) | 1 : 3.4 | 1 : 2.3 | 0.43 | 1 : 5.5 | 1 : 6.2 | 0.75 |
Maximum diameter, mm | 13.0 (8.5–23.5) | 13.0 (9.0–16.5) | 0.42 | 16.0 (10.0–25.5) | 12.0 (8.3–15.0) | < 0.01 |
Component | Â | Â | 0.04 | Â | Â | 0.05 |
 Solid | 44 (77.2) | 31 (93.9) |  | 18 (69.2) | 32 (88.9) |  |
 Partially cystic | 13 (22.8) | 2 (6.1) |  | 8 (30.8) | 4 (11.1) |  |
Echogenicity | Â | Â | 0.12 | Â | Â | 0.92 |
 Markedly hypoechoic | 10 (17.5) | 11 (33.3) |  | 6 (23.1) | 7 (19.4) |  |
 Hypoechoic | 29 (50.9) | 17 (51.5) |  | 13 (50.0) | 20 (55.6) |  |
 Iso-echoic | 14 (24.6) | 2 (6.1) |  | 5 (19.3) | 7 (19.4) |  |
 Hyperechoic | 1 (1.8) | 0 (0) |  | 1 (3.8) | 0 (0) |  |
 Mix-echoic | 3 (5.3) | 3 (9.1) |  | 1 (3.8) | 2 (5.6) |  |
Margin |  |  | 0.02 |  |  | < 0.01 |
 Microlobulated | 8 (14.0) | 13 (39.4) |  | 2 (7.7) | 18 (50.0) |  |
 Irregular | 25 (43.9) | 12 (36.4) |  | 8 (30.8) | 12 (33.3) |  |
 Well circumscribed | 24 (42.1) | 8 (24.2) |  | 16 (61.5) | 6 (16.7) |  |
Shape |  |  | 0.67 |  |  | < 0.01 |
 Wider than taller | 47 (82.5) | 7 (21.2) |  | 19 (73.1) | 8 (22.2) |  |
 Taller than wider | 10 (17.5) | 26 (78.8) |  | 7 (26.9) | 28 (77.8) |  |
Location | Â | Â | 0.67 | Â | Â | 0.28 |
 Upper | 8 (14.0) | 6 (18.2) |  | 8 (30.8) | 14 (38.9) |  |
 Middle | 32 (56.1) | 21 (63.6) |  | 11 (42.3) | 16 (44.4) |  |
 Lower | 12 (21.1) | 4 (12.1) |  | 7 (26.9) | 4 (11.1) |  |
 Isthmus | 5 (8.8) | 2 (6.1) |  | 0 (0) | 2 (5.6) |  |
Microcalcification |  |  | < 0.01 |  |  | < 0.01 |
 Yes | 5 (8.8) | 19 (57.6) |  | 2 (7.7) | 30 (83.3) |  |
 No | 52 (91.2) | 14 (42.4) |  | 24 (92.3) | 6 (16.7) |  |
Blood flow | Â | Â | 0.60 | Â | Â | 0.63 |
 Grade 0 | 21 (36.8) | 12 (36.4) |  | 13 (50.0) | 15 (41.7) |  |
 Grade 1 | 26 (45.6) | 18 (54.5) |  | 6 (23.1) | 13 (36.1) |  |
 Grade 2 | 4 (7.0) | 2 (6.1) |  | 4 (15.4) | 6 (16.6) |  |
 Grade 3 | 6 (10.5) | 1 (3.0) |  | 3 (11.5) | 2 (5.6) |  |
Imprinted gene detection |  |  | < 0.01 |  |  | < 0.01 |
 Grade 0 | 26 (45.6) | 0 (0) |  | 16 (61.5) | 0 (0) |  |
 Grade I | 22 (38.6) | 1 (3.0) |  | 5 (19.2) | 4 (11.1) |  |
 Grade II | 5 (8.8) | 10(30.3) |  | 3 (11.5) | 12 (33.3) |  |
 Grade III | 4 (7.0) | 14 (42.4) |  | 2 (7.8) | 17 (47.3) |  |
 Grade IV | 0 (0) | 8 (24.3) |  | 0 (0) | 3 (8.3) |  |
Cytopathology |  |  | < 0.01 |  |  | < 0.01 |
 Benign (Category II) | 20 (35.0) | 1 (3.0) |  | 17 (65.4) | 0 (0) |  |
 AUS (Category III) | 35 (61.4) | 9 (27.3) |  | 5 (19.2) | 3 (8.3) |  |
 FN (Category IV) | 1 (1.8) | 4 (12.1) |  | 4 (15.4) | 4 (11.1) |  |
 SUS (Category V) | 1 (1.8) | 7 (21.2) |  | 0 (0) | 24 (66.7) |  |
 Malignant (Category VI) | 0 (0) | 12 (36.4) |  | 0 (0) | 5 (13.9) |  |