- Descriptive characteristics of the study participants overall and by initial risk status (N=230).
| Variables | Total | Initial risk | P-values | ||
|---|---|---|---|---|---|
| Low (n=104) | Intermediate (n=71) | High (n=55) | |||
| Age (years), mean±SD | 41.33±14.53 | 41.14±12.19 | 38.44±15.40 | 45.40±16.64 | 0.03 |
| Age | |||||
| ≤55 years | 191 (83.0) | 90 (86.5) | 61 (85.9) | 40 (72.7) | 0.06 |
| >55 years | 39 (17.0) | 14 (13.5) | 10 (14.1) | 15 (27.3) | |
| Gender | |||||
| Male | 60 (26.1) | 13 (12.5) | 25 (35.2) | 22 (40.0) | <0.0001 |
| Female | 170 (73.9) | 91 (87.5) | 46 (64.8) | 33 (60.0) | |
| Pathology | |||||
| Papillary | 213 (92.6) | 99 (95.2) | 65 (91.5) | 49 (89.1) | 0.29 |
| Follicular or oncocytic | 17 (7.4) | 5 (4.8) | 6 (8.5) | 6 (10.9) | |
| N | |||||
| N0 or NX | 156 (67.8) | 100 (96.2) | 28 (39.4) | 28 (50.9) | <0.0001 |
| N1 | 74 (32.2) | 4 (3.8) | 43 (60.6) | 27 (49.1) | |
| M | |||||
| M0 | 210 (91.3) | 104 (100) | 71 (100) | 35 (63.6) | <0.0001 |
| M1 | 20 (8.7) | 0 (0.0) | 0 (0.0) | 20 (36.4) | |
| Vascular invasion | 54 (26.5) | 0 (0.0) | 31 (50.8) | 23 (48.9) | <0.0001 |
| Margin involvement | 41 (20.9) | 6 (6.6) | 17 (27.9) | 18 (40.9) | <0.0001 |
| Extrathyroidal extension | 34 (15.7) | 0 (0.0) | 13 (19.04) | 21 (42.0) | <0.0001 |
| Variant | |||||
| Non papillary | 15 (8.1) | 5 (5.8) | 4 (7.3) | 6 (13.6) | 0.001 |
| PTC-low risk variants | 157 (84.9) | 81 (94.2) | 46 (83.6) | 30 (68.2) | |
| PTC-high risk variants | 13 (7.0) | 0 (0.0) | 5 (9.1) | 8 (18.2) | |
| Multifocality | 106 (49.5) | 40 (40.4) | 37 (55.2) | 29 (60.4) | 0.04 |
| Size of the largest focus (cm), median (Q1, Q3) | 2.3 (1.0, 4.0) | 1.5 (0.8, 3.0) | 3.0 (2.0, 4.0) | 3.5 (1.5, 5.0) | <0.0001 |
| Size of the largest focus | |||||
| ≤4 cm | 164 (81.2) | 83 (86.5) | 50 (82.0) | 31 (68.9) | 0.04 |
| >4 cm | 38 (18.8) | 13 (13.5) | 11 (18.0) | 14 (31.1) | |
| Size of the largest focus | |||||
| ≤2.3 cm | 104 (51.5) | 65 (67.7) | 21 (34.4) | 18 (40.0) | <0.0001 |
| >2.3 cm | 98 (48.5) | 31 (32.3) | 40 (65.6) | 27 (60.0) | |
| Stage at diagnosis | |||||
| 1 | 202 (87.8) | 104 (100.0) | 65 (91.5) | 33 (60.0) | <0.0001 |
| 2 | 18 (7.8) | 0 (0.0) | 6 (8.5) | 12 (21.8) | |
| 3 | 5 (2.2) | 0 (0.0) | 0 (0.0) | 5 (9.1) | |
| 4b | 5 (2.2) | 0 (0.0) | 0 (0.0) | 5 (9.1) | |
| Type of surgery | |||||
| Lobectomy/hemithyroidectomy | 11 (4.8) | 8 (7.7) | 1 (1.4) | 2 (3.6) | 0.14 |
| Total or subtotal thyroidectomy | 219 (95.2) | 96 (92.3) | 70 (98.6) | 53 (96.4) | |
| Given at least one RAI, dose ≥30 mCi | 183 (79.6) | 67 (64.4) | 67 (94.4) | 49 (89.1) | <0.0001 |
Values are presented as numbers and precentages (%), mean ± standard deviation (SD), or median (first quartile [Q1], third quartile [Q3]).
PTC: papillary thyroid cancer, RAI: radioactive iodine