Table 2 Clinical and ultrasound characteristics predicting malignancy of ACR TI-RADS 4 and 5 thyroid nodules
Characteristic | Training (n = 219) | Validation (n = 93) | ||||
|---|---|---|---|---|---|---|
Benign (n = 66) | Malignant (n = 153) | P value | Benign (n = 27) | Malignant (n = 66) | P value | |
Sex | 0.468 | 0.032 | ||||
Male | 11 (16.7) | 32 (20.9) | 2 (7.4) | 18 (27.3) | ||
Female | 55 (83.3) | 121 (79.1) | 25 (92.6) | 48 (72.7) | ||
Age (years) | 0.029 | 0.620 | ||||
Mean ± SD | 42.83 ± 10.94 | 39.25 ± 11.11 | 40.85 ± 11.24 | 39.62 ± 10.64 | ||
Range | 19–69 | 18–67 | 21–64 | 18–60 | ||
Tumor size (mm), median (IQR) | 12 (8–20) | 10 (8–15) | 0.048 | 22 (17–29) | 10 (6–15) | < 0.001 |
Primary site | 0.033 | 0.589 | ||||
Right | 31 (47.0) | 86 (56.2) | 15 (55.6) | 30 (45.5) | ||
Left | 35 (53.0) | 61 (39.9) | 11 (40.7) | 31 (47.0) | ||
Isthmus | 0 (0) | 6 (3.9) | 1 (3.7) | 5 (7.6) | ||
Composition | 0.032 | 0.029 | ||||
Mixed cystic and solid | 11 (16.7) | 11 (7.2) | 9 (33.3) | 9 (13.6) | ||
Solid or almost completely solid | 55 (83.3) | 142 (92.8) | 18 (66.7) | 57 (86.4) | ||
Echogenicity | 0.414 | 0.406 | ||||
Hyperechoic or isoechoic | 1 (1.5) | 3 (2.0) | 0 (0.0) | 0 (0.0) | ||
Hypoechoic | 63 (95.5) | 149 (97.4) | 27 (100.0) | 65 (98.5) | ||
Very hypoechoic | 2 (3.0) | 1 (0.7) | 0 (0.0) | 1 (1.5) | ||
Shape | < 0.001 | 0.014 | ||||
Wider-than-tall | 47 (71.2) | 57 (37.3) | 21 (77.8) | 33 (50.0) | ||
Taller-than wide | 19 (28.8) | 96 (62.7) | 6 (22.2) | 33 (50.0) | ||
Margin | < 0.001 | 0.001 | ||||
Smooth or ill-defined | 27 (40.9) | 12 (7.8) | 8 (29.6) | 2 (3.0) | ||
Lobulated or irregular | 39 (59.1) | 138 (90.2) | 19 (70.4) | 61 (92.4) | ||
Extra-thyroidal extension | 0 (0) | 3 (2) | 0 (0.0) | 3 (4.5) | ||
Echogenic foci | < 0.001 | 0.298 | ||||
None or large comet-tail artifacts | 35 (53.0) | 42 (27.5) | 11 (40.7) | 19 (28.8) | ||
Macrocalcifications | 8 (12.1) | 12 (7.8) | 2 (7.4) | 2 (3.0) | ||
Punctate echogenic foci | 23 (34.8) | 99 (64.7) | 14 (51.9) | 45 (68.2) | ||
TI-RADS risk level | < 0.001 | < 0.001 | ||||
TR4 | 28 (42.4) | 18 (11.8) | 15 (55.6) | 7 (10.6) | ||
TR5 | 38 (57.6) | 135 (88.2) | 12 (44.4) | 59 (89.4) | ||
Enhancement direction | < 0.001 | < 0.001 | ||||
Scattered | 31 (47.0) | 26 (17.0) | 15 (55.6) | 11 (16.7) | ||
Centripetal or centrifugal | 35 (53.0) | 127 (83.0) | 12 (44.4) | 55 (83.3) | ||
Enhancement pattern | 0.001 | 0.430 | ||||
Homogeneous | 22 (33.3) | 22 (14.4) | 5 (18.5) | 8 (12.1) | ||
Heterogeneous | 44 (66.7) | 131 (85.6) | 22 (81.5) | 58 (87.9) | ||
Peak intensity | 0.062 | 0.305 | ||||
None- or iso-enhancement | 18 (27.3) | 25 (16.3) | 7 (25.9) | 11 (16.7) | ||
Hypo- or Hyper-enhancement | 48 (72.7) | 128 (83.7) | 20 (74.1) | 55 (83.3) | ||
Ring enhancement | < 0.001 | < 0.001 | ||||
Absent | 47 (71.2) | 145 (94.8) | 15 (55.6) | 60 (90.9) | ||
Present | 19 (28.8) | 8 (5.2) | 12 (44.4) | 6 (9.1) | ||
BMUS Rad-score, median (IQR) | 0.64 (0.15–0.97) | 1.05 (0.73–1.35) | < 0.001 | 0.49 (0.13–1.05) | 0.95 (0.65–1.37) | 0.001 |
CEUS Rad-score, median (IQR) | 0.58 (0.03–1.06) | 1.18 (0.85–1.40) | < 0.001 | 0.64 (0.07–0.70) | 1.15 (0.87–1.40) | < 0.001 |