Table 1.
Metastatic characteristics of evaluated thyroid tumors
| NIFTP | FVPTC | Mixed histology | p value | |
|---|---|---|---|---|
| Number of cases (total) | 47 (37%) | 28 (22%) | 45 (35%) | |
| Mean and range time of patient follow-up (in days) | 611.17 | 714.63 | 707.71 | 0.74 |
| (0–2310.0) | (0–2275.0) | (0–2104.0) | ||
| Average tumor size in cm (largest focus) | 1.72 | 1.43 | 2.10 | 0.20 |
| Average number of foci | 1.42 | 1.71 | 1.98 | 0.01 |
| Number of cases with nodal evaluation | 13/47 (27.7%) | 17/28 (60.7%) | 29/45 (64.4%) | <0.01 |
| Average number of LNs examined | 7.58 | 11.31 | 25.4 | <0.01 |
| Number of cases with positive lymph nodes | 0/47 (0%) | 7/28 (25.0%) | 17/45 (37.7%) | 0.43 |
| Location of positive lymph nodesa,b | pN1a = 0 cases | pN1a = 3 cases (10.7%) | pN1a = 5 cases (11.1%) | <0.01 |
| pN1b = 0 cases | pN1b = 4 cases (14.2%) | pN1b = 12 cases (26.6%) | ||
| Number of positive nodal cases with extra-thyroidal extension | 0/0 (0%) | 1/7 (14.2%) | 12/17 (70.6%) | 0.02 |
a pN1a metastasis to level VI (pretracheal, paratracheal and prelaryngeal/Delphian, perithyroidal) lymph nodes
b pN1b metastasis to unilateral, bilateral or contralateral cervical (levels I, II, III, IV, V) or retropharyngeal or superior mediastinal lymph nodes (level VII)