Table 2.
The frequency and risk of malignancy of thyroid nodules according to internal content and echogenicity
| Nodule echogenicity | Overall (n=1,000) | Benign nodule (n=883) | Malignant nodule (n=117) | Malignancy risk (%) | P-valuea) |
|---|---|---|---|---|---|
| Hypoechogenicity | 257 (25.7) | 189 (21.4) | 68 (58.1) | 26.5 | <0.001 |
| Purely solid | 222 (86.4) | 156 (82.5) | 66 (97.1) | 29.7 | 0.003 |
| Minimally cystic | 9 (3.5) | 9 (4.8) | 0 | 0.0 | 0.118 |
| Partially cystic | 26 (10.1) | 24 (12.7) | 2 (2.9) | 7.7 | 0.022 |
| Isohyperechogenicity | 743 (74.3) | 694 (78.6) | 49 (41.9) | 6.6 | <0.001 |
| Purely solid | 508 (68.4) | 466 (67.1) | 42 (85.7) | 8.3 | 0.007 |
| Minimally cystic | 52 (7) | 50 (7.2) | 2 (4.1) | 3.8 | 0.568 |
| Partially cystic | 183 (24.6) | 178 (25.7) | 5 (10.2) | 2.7 | 0.015 |
Values are presented as number (%).
a)
The chi-square test or Fisher exact test was used to evaluate associations between each category of internal content, echogenicity, and the final diagnosis.