Table 1.
Baseline characteristics of patients in the training and validation cohorts
| Characteristic | Training cohort (n = 169) |
Validation cohort (n = 111) |
P-value |
|---|---|---|---|
| Recurrence | 0.941 | ||
| Absence | 115 (68.0) | 76 (68.5) | |
| Presence | 54 (32.0) | 35 (31.5) | |
| Clinicopathologic features | |||
| Age (years)a | 40.25 ± 13.71 | 41.47 ± 13.49 | 0.466 |
| Sex | 0.479 | ||
| Male | 54 (32.0) | 40 (36.0) | |
| female | 115 (68.0) | 71 (64.0) | |
| Tumor size (mm)a | 20.36 ± 10.20 | 22.31 ± 11.85 | 0.156 |
| Bilaterality | 0.572 | ||
| Absence | 85 (50.3) | 52 (46.8) | |
| Presence | 84 (49.7) | 59 (53.2) | |
| Multifocality | 0.383 | ||
| Absence | 65 (38.5) | 37 (33.3) | |
| Presence | 104 (61.5) | 74 (66.7) | |
| Extrathyroidal extension | 0.161 | ||
| Absence | 13 (7.7) | 4 (3.6) | |
| Presence | 156 (92.3) | 107 (96.4) | |
| Number of metastatic LNb | 11 (5–19) | 10 (4–19) | 0.874 |
| Concomitant thyroid disease | 0.107 | ||
| Neither | 43 (25.4) | 30 (27.0) | |
| Nodular goiter | 80 (47.3) | 62 (55.9) | |
| Hashimoto’s thyroiditis | 41 (24.3) | 14 (12.6) | |
| Both | 5 (3.0) | 5 (4.5) | |
| Surgical option | 0.302 | ||
| Total thyroidectomy | 140 (82.8) | 97 (87.4) | |
| Subtotal or semi-total thyroidectomy | 29 (17.2) | 14 (12.6) | |
| T stage | 0.697 | ||
| T1a | 3 (1.8) | 0 (0) | |
| T1b | 6 (3.6) | 3 (2.7) | |
| T2 | 2 (1.2) | 1 (0.9) | |
| T3 | 137 (81.1) | 96 (86.5) | |
| T4a | 21 (12.4) | 11 (9.9) | |
| N stage | 0.897 | ||
| N0 | 17 (10.1) | 10 (9.0) | |
| N1a | 23 (13.6) | 17 (15.3) | |
| N1b | 129 (76.3) | 84 (75.7) | |
| 131I radiotherapy | 0.359 | ||
| Not received | 88 (52.1) | 64 (57.7) | |
| Received | 81 (47.9) | 47 (42.3) | |
| Family history | 0.385 | ||
| Absence | 159 (94.1) | 107 (96.4) | |
| Presence | 10 (5.9) | 4 (3.6) | |
| CT features | |||
| Shape | 0.594 | ||
| Regular | 30 (17.8) | 17 (15.3) | |
| Irregular | 139 (82.2) | 94 (84.7) | |
| Margin | 0.588 | ||
| Well-defined | 24 (14.2) | 19 (17.1) | |
| Ill-defined | 145 (85.8) | 92 (82.9) | |
| Calcification | 0.172 | ||
| Absence | 81 (47.9) | 44 (39.6) | |
| Presence | 88 (52.1) | 67 (60.4) | |
| CT-reported LN status | 0.291 | ||
| Negative | 35 (20.7) | 29 (26.1) | |
| Positive | 134 (79.3) | 82 (73.9) |
Unless otherwise indicated, data are the number of patients and data in parentheses are percentages
a Data are means ± standard deviation
b Data are medians, with interquartile range in parentheses
CT: computed tomography; LN: lymph nodes