Table 2. Baseline Characteristics of 1310 Asymptomatic Thyroid Nodules.
| Benign | Malignant | P | |
|---|---|---|---|
| No. of nodules | 731 | 579 | |
| Mean age (years) | 51.2 ± 12.0 | 47.6 ± 12.8 | < 0.001 |
| Age (years) | 0.004 | ||
| < 20 or > 60 | 165 (22.6%) | 94 (16.2%) | |
| 20–60 | 566 (77.4%) | 485 (83.8%) | |
| Gender | 0.014 | ||
| Male | 149 (20.4%) | 152 (26.3%) | |
| Female | 582 (79.6%) | 427 (73.7%) | |
| 1st degree family history | 0.011 | ||
| Yes | 48 (6.6%) | 63 (10.9%) | |
| One | 40 (5.5%) | 57 (9.8%) | |
| Two | 8 (1.1%) | 6 (1.0%) | |
| No | 683 (93.4%) | 516 (89.1%) | |
| Mean nodule size (mm) | 16.0 ± 9.6 | 9.8 ± 6.4 | < 0.001 |
| Multiplicity | 0.044 | ||
| Solitary | 222 (30.4%) | 207 (35.8%) | |
| Multiple | 509 (69.6%) | 372 (64.2%) | |
| Serum TSH value | |||
| Mean TSH level (mIU/L) | 1.6 ± 0.9 | 1.7 ± 0.9 | 0.075 |
| TSH grade | 0.024 | ||
| 0.3–1.39 | 381 (52.1%) | 258 (44.6%) | |
| 1.4–2.49 | 242 (33.1%) | 220 (38.0%) | |
| 2.5–4.99 | 108 (14.8%) | 101 (17.4%) | |
| US final assessment | < 0.001 | ||
| Probably benign | 566 (77.4%) | 49 (8.5%) | |
| Suspicious malignant | 165 (22.6%) | 530 (91.5%) |
1st degree = first-degree, TSH = thyroid stimulating hormone, US = ultrasonography