Table 1. Summary of Demographic and Ultrasonography Features.
| Characteristics | Benign (n = 250) | Metastatic (n = 586) | Malignancy Rate (%) | P | |
|---|---|---|---|---|---|
| Sex | < 0.001 | ||||
| Male | 60 (24.0) | 224 (38.2) | |||
| Female | 190 (76.0) | 362 (61.8) | |||
| Age, year* | 47.86 ± 12.85 | 47.53 ± 14.21 | 0.063 | ||
| Location | 0.051 | ||||
| Level II | 25 (10.0) | 48 (8.2) | |||
| Level III | 70 (28.0) | 214 (36.5) | |||
| Level IV | 144 (57.6) | 306 (52.2) | |||
| Level V | 5 (2.0) | 3 (0.5) | |||
| Level VI | 6 (2.4) | 15 (2.5) | |||
| Short diameter, cm* | 0.419 ± 0.16 | 0.603 ± 0.39 | < 0.001 | ||
| Long diameter, cm* | 1.144 ± 0.56 | 1.197 ± 0.67 | 0.001 | ||
| Size enlargement | 62 (24.8) | 284 (48.5) | 82.1 | < 0.001 | |
| L/S ratio < 1.5 | 24 (9.6) | 140 (23.9) | 85.4 | < 0.001 | |
| L/S ratio < 2 | 74 (29.6) | 308 (52.6) | 80.6 | < 0.001 | |
| Margin | < 0.001 | ||||
| Smooth | 180 (72.0) | 173 (29.5) | 49.0 | ||
| Irregular | 70 (28.0) | 413 (70.5) | 85.5 | ||
| Orientation | 0.049 | ||||
| Parallel | 240 (96.0) | 541 (92.3) | 69.3 | ||
| Nonparallel | 10 (4.0) | 45 (7.7) | 81.8 | ||
| Eccentric cortical thickening | 48 (28.9) | 50 (58.8) | 33.9 | < 0.001 | |
| Hilum | < 0.001 | ||||
| Absent | 84 (33.6) | 501 (85.5) | 85.6 | ||
| Present | 166 (66.4) | 85 (14.5) | 33.9 | ||
| Cystic changes | 1 (0.4) | 151 (25.8) | 99.3 | < 0.001 | |
| Punctate echogenic foci | 33 (13.2) | 304 (51.9) | 90.2 | < 0.001 | |
| Large echogenic foci | 8 (3.2) | 38 (6.5) | 82.6 | 0.057 | |
| Abnormal vascularity | 15 (6.0) | 386 (65.9) | 96.4 | < 0.001 | |
| Cortical hyperechogenecity | 33 (13.2) | 491 (83.8) | 93.7 | < 0.001 | |
Data are expressed as the number of cases with percentages in parentheses unless otherwise indicated. *Data are expressed as mean ± standard deviation. L/S ratio = long-to-short diameter ratio