Table 2.
Distribution of follicular thyroid neoplasms among the ultrasound-based malignancy risk stratification systems
| FTA | FTC | p | Minimally invasive | Encapsulated angioinvasive | Widely invasive | p | ||
|---|---|---|---|---|---|---|---|---|
| Ultrasound-based malignancy risk stratification systems | ||||||||
| ATA | Total classification | 251 | 60 | p < 0.001 | 42 | 12 | 6 | p = 0.870 |
| Benign | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |||
| Very low suspicion | 52 (20.7) | 1 (1.7) | 1 (2.4) | 0 (0) | 0 (0) | |||
| Low suspicion | 168 (66.9) | 45 (75.0) | 31 (73.8) | 9 (75.0) | 5 (83.3) | |||
| Intermediate suspicion | 28 (11.2) | 9 (15.0) | 7 (16.7) | 1 (8.3) | 1 (16.7) | |||
| High suspicion | 3 (1.2) | 5 (8.3) | 3 (7.1) | 2 (16.7) | 0 (0) | |||
| AACE/ACE/AME | Total classification | 260 | 62 | p < 0.001 | 44 | 12 | 6 | p = 0.577 |
| Low-risk | 10 (3.8) | 1 (1.6) | 1 (2.3) | 0 (0) | 0 (0) | |||
| Intermediate-risk | 242 (93.1) | 51 (82.3) | 37 (84.1) | 9 (75.0) | 5 (83.3) | |||
| High-risk | 8 (3.1) | 10 (16.1) | 6 (13.6) | 3 (25.0) | 1 (16.7) | |||
| K-TIRADS | Total classification | 261 | 66 | p = 0.002 | 48 | 12 | 6 | p = 0.685 |
| Benign | 8 (3.1) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |||
| Low suspicion | 212 (81.2) | 46 (69.7) | 32 (66.7) | 9 (75.0) | 5 (83.3) | |||
| Intermediate suspicion | 38 (14.6) | 15 (22.7) | 13 (27.0) | 1 (8.3) | 1 (16.7) | |||
| High suspicion | 3 (1.1) | 5 (7.6) | 3 (6.3) | 2 (16.7) | 0 (0) | |||
| EU-TIRADS | Total classification | 256 | 62 | p < 0.001 | 46 | 10 | 6 | p = 0.686 |
| Benign | 4 (1.6) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |||
| Low risk | 211 (82.4) | 41 (66.1) | 31 (67.4) | 7 (70.0) | 3 (50.0) | |||
| Intermediate risk | 31 (12.1) | 7 (11.3) | 5 (10.9) | 1 (10.0) | 1 (16.7) | |||
| High risk | 10 (3.9) | 14 (22.6) | 10 (21.7) | 2 (20.0) | 2 (33.3) | |||
| ACR-TIRADS | Total classification | 262 | 67 | p < 0.001 | 48 | 12 | 7 | p = 0.736 |
| ACR-TR1 | 4 (1.5) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |||
| ACR-TR2 | 58 (22.1) | 4 (6.0) | 4 (8.3) | 0 (0) | 0 (0) | |||
| ACR-TR3 | 148 (56.6) | 37 (55.2) | 25 (52.1) | 7 (58.3) | 5 (71.4) | |||
| ACR-TR4 | 49 (18.7) | 21 (31.3) | 16 (33.3) | 3 (25.0) | 2 (28.6) | |||
| ACR-TR5 | 3 (1.1) | 5 (7.5) | 3 (6.3) | 2 (16.7) | 0 (0) | |||
| C-TIRADS | Total classification | 262 | 67 | p < 0.001 | 48 | 12 | 7 | p = 0.075 |
| C-TR2 | 8 (3.1) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |||
| C-TR3 | 61 (23.3) | 6 (9.0) | 6 (12.5) | 0 (0) | 0 (0) | |||
| C-TR4A | 181 (69.1) | 43 (64.2) | 32 (66.7) | 7 (58.3) | 4 (57.1) | |||
| C-TR4B | 9 (3.4) | 10 (14.9) | 6 (12.5) | 2 (16.7) | 2 (28.6) | |||
| C-TR4C | 3 (1.1) | 5 (7.5) | 4 (8.3) | 1 (8.3) | 0 (0) | |||
| C-TR5 | 0 (0) | 3 (4.5) | 0 (0) | 2 (16.7) | 1 (14.3) | |||
Values are presented as number (%)
Abbreviations: FTA follicular thyroid adenoma; FTC follicular thyroid carcinoma; ATA 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer; AACE/ACE/AME American Association of Clinical Endocrinologists, American College of Endocrinology, and Associazione Medici Endocrinology Medical Guidelines for Clinical Practice for the Diagnosis and Management of Thyroid Nodules (2016 Update); EU-TIRADS European Thyroid Association Guidelines for Ultrasound Malignancy Risk Stratification of Thyroid Nodules in Adults; K-TIRADS Revised Korean Society of Thyroid Radiology Consensus Statement and Recommendations; ACR-TIRADS American College of Radiology Thyroid Imaging Reporting and Data System; C-TIRADS 2020 Chinese Guidelines for Ultrasound Malignancy Risk Stratification of Thyroid Nodules