Characteristics of Included Cohort
| Characteristic | Total cohort | Confined | mETE | P* (univariate analysis) |
|---|---|---|---|---|
| Patients | 721 | 644 (89.3) | 77 (10.7) | |
| Sex (male) | 154 (21.4) | 145 (22.5) | 9 (11.7) | 0.041 |
| Age (y) | 47.95 ± 12.83 | 48.02 ± 12.77 | 47.38 ± 13.42 | 0.678 |
| Median follow-up (y)† | 9.30 (95% CI, 8.89–9.94) | 8.94 (95% CI, 8.40–9.43) | 12.85 (95% CI, 10.76–14.38) | 0.002 |
| Extent of thyroidectomy | <0.001 | |||
| Hemithyroidectomy | 18 (2.5) | 18 (2.8) | 0 (0.0) | |
| Subtotal thyroidectomy | 126 (17.5) | 125 (19.4) | 1 (1.3) | |
| Total thyroidectomy | 577 (80.0) | 501 (77.8) | 76 (98.7) | |
| Lymph node dissection | <0.001 | |||
| No lymph nodes resected | 505 (70.0) | 472 (73.3) | 33 (42.9) | |
| Node picking | 51 (7.1) | 46 (7.1) | 5 (6.5) | |
| Central compartment node dissection | 120 (16.6) | 93 (14.4) | 27 (35.1) | |
| Central and lateral neck node dissection | 45 (6.2) | 33 (5.1) | 12 (15.6) | |
| Number of removed lymph nodes | 0 (IQR, 0–1) | 0 (IQR, 0–0] | 2 (IQR, 0–10) | <0.001 |
| Adjuvant RAI | 540 (74.9) | 463 (71.9) | 77 (100.0) | <0.001 |
| Cumulative RAI activity (GBq) | 3.00 (IQR, 0.00–6.00) | 3.00 (IQR, 0.00–4.00) | 6.00 (IQR, 3.00–10.00) | <0.001 |
| Number of RAIs | 1.00 (IQR, 0.00–2.00) | 1.00 (IQR, 0.00–1.00) | 1.00 (IQR, 1.00–2.00) | <0.001 |
| Pre-RAI TSH (μU/mL) | 43.06 (IQR, 15.62–77.26) | 39.17 (IQR, 13.24–76.89) | 59.36 (IQR, 42.20–77.72) | 0.001 |
| Pre-RAI thyroglobulin (ng/mL) | 2.30 (IQR, 0.62–8.45) | 2.50 (IQR, 0.60–8.67) | 2.20 (IQR, 0.80–7.00) | 0.935 |
*Determined with Fisher exact test for categoric variables and Wilcoxon test for continuous variables.
↵†Calculated by reverse Kaplan–Meier test.
IQR = interquartile range.
Qualitative data are number followed by percentage; continuous data are mean ± SD, or median followed by 95% CI or IQR.