Table 2.
Comparison between groups: FNA+ vs. FNA−, Bethesda II vs. Bethesda IV-V-VI, benign vs. malignant.
| FNA+ | FNA− | p | Bethesda II | Bethesda IV-V-VI | p | Benign | Malignant | p | |
|---|---|---|---|---|---|---|---|---|---|
| n = 2308 | n = 501 | n = 1874 | n = 194 | n = 450 | n = 135 | ||||
| Age (years) | 51.5 ± 14.1 | 53.4 ± 14.7 | 0.011 | 51.7 ± 13.8 | 50.1 ± 16.3 | 0.224 | 49.4 ± 13.4 | 46.8 ± 15.8 | 0.073 |
| Sex (%) | 0.719 | 0.122 | 0.637 | ||||||
| Male | 13.8 | 14.4 | 12 | 16.1 | 17 | 19 | |||
| Female | 86.2 | 85.6 | 88 | 83.9 | 83 | 81 | |||
| Nodule size (mm) | 24.2 ± 11.7 | 10.9 ± 7.9 | <0.001 | 24.1 ± 11.7 | 25.6 ± 12.1 | 0.074 | 32.8 ± 12.1 | 24.4 ± 11.2 | <0.001 |
| Nodule size (mm) | <0.001 | 0.449 | <0.001 | ||||||
| <20 | 41 | 87.5 | 41.2 | 36.5 | 14.7 | 38 | |||
| ≥20–<40 | 46.4 | 10.8 | 46.3 | 50 | 52.8 | 52.9 | |||
| ≥40 | 12.6 | 1.6 | 12.6 | 13.5 | 32.5 | 9.1 | |||
| Palpable (%) | <0.001 | 0.009 | 0.055 | ||||||
| Yes | 56 | 17 | 55.8 | 68 | 73.1 | 62.2 | |||
| No | 44 | 83 | 44.2 | 32 | 26.9 | 37.8 | |||
| Echogenicity (%) | <0.001 | 0.392 | 0.012 | ||||||
| Hyperechoic | 7.4 | 11.8 | 7.7 | 7 | 8.4 | 5.4 | |||
| Isoechoic | 37.6 | 16.7 | 38.4 | 32 | 33.6 | 14.3 | |||
| Hypoechoic | 55 | 71.5 | 53.9 | 61 | 58 | 80.4 | |||
| Composition (%) | 0.002 | <0.001 | <0.001 | ||||||
| Mixed cystic and solid | 31.2 | 23.5 | 34.2 | 16.5 | 31 | 13.1 | |||
| Solid | 68.8 | 76.5 | 65.8 | 83.5 | 69 | 86.9 | |||
| Margins (%) | 0.250 | 0.001 | <0.001 | ||||||
| Regular | 95.8 | 97.1 | 96.3 | 90.7 | 96.9 | 84.5 | |||
| Irregular | 4.2 | 2.9 | 3.7 | 9.3 | 3.1 | 15.5 | |||
| Microcalcifications (%) | <0.001 | <0.001 | <0.001 | ||||||
| Absent | 91.7 | 98.4 | 93 | 81.6 | 90.2 | 76.1 | |||
| Present | 8.3 | 1.6 | 7 | 18.4 | 9.8 | 23.9 |
Data are the mean ± SD and the number (percentage) for categorical variables. FNA: fine-needle aspiration; OR: odds ratio.