Table 1.
Clinico-Pathologic Characteristics and BRAF/NRAS Mutation in Unifocal Encapsulated Papillary Thyroid Carcinoma According to the Nodal Status at the Time of Initial Surgery
| All patients (n = 235) | N0/Nx (n = 208) | N1 (n = 27) | p-Values | |
|---|---|---|---|---|
| Architectural patterns | ||||
| Percentage of papillae | ||||
| 0% | 127 (54%) | 127 (61%) | 0 (0%) | <0.001 |
| 0.1–0.9% | 31 (13%) | 31 (15%) | 0 (0%) | |
| 1–9% | 14 (6%) | 13 (6%) | 1 (4%) | |
| 10–24% | 6 (3%) | 4 (2%) | 2 (7%) | |
| 25–49% | 5 (2%) | 5 (2%) | 0 (0%) | |
| ≥50% | 52 (22%) | 28 (13%) | 24 (89%) | |
| Percentage of follicles | ||||
| 0–24% | 52 (22%) | 31 (15%) | 21 (78%) | <0.001 |
| 25–49% | 6 (3%) | 3 (1%) | 3 (11%) | |
| ≥50% | 177 (75%) | 174 (84%) | 3 (11%) | |
| Percentage of solid growth | ||||
| 0–24% | 222 (94%) | 195 (94%) | 27 (100%) | 0.409 |
| 25–49% | 5 (2%) | 5 (2%) | 0 (0%) | |
| ≥50% | 8 (3%) | 8 (4%) | 0 (0%) | |
| BRAF and NRAS mutations (n = 100) | ||||
| BRAF/NRAS | ||||
| Positive BRAFV600E | 24 (24%) | 10 (12%) | 14 (74%) | <0.001 |
| Positive NRASQ61R | 26 (26%) | 26 (32%) | 0 (0%) | |
| Negative | 50 (50%) | 45 (56%) | 5 (26%) | |
| Other characteristics | ||||
| Sex | ||||
| Female | 156 (66%) | 141 (68%) | 15 (56%) | 0.206 |
| Male | 79 (34%) | 67 (32%) | 12 (44%) | |
| Age, median (range) | 46 (8–82) | 47 (8–82) | 36 (22–59) | <0.001 |
| Tumor size, cm, median (range) | 2.2 (0.1–7.5) | 2.3 (0.1–7.5) | 2.0 (0.3–4.7) | 0.088 |
| Type of surgery (n = 234) | ||||
| Lobectomy | 102 (44%) | 94 (45%) | 8 (30%) | 0.15 |
| Total thyroidectomy | 132 (56%) | 113 (55%) | 19 (70%) | |
| Capsular invasion | ||||
| Absent | 166 (71%) | 154 (74%) | 12 (44%) | <0.001 |
| Focal | 57 (24%) | 47 (23%) | 10 (37%) | |
| Extensive | 12 (5%) | 7 (3%) | 5 (19%) | |
| Vascular invasion | ||||
| Absent | 212 (90%) | 186 (89%) | 26 (96%) | 0.481 |
| Focal | 16 (7%) | 15 (7%) | 1 (4%) | |
| Extensive | 7 (3%) | 7 (3%) | 0 (0%) | |
| Extrathyroidal extension | ||||
| Absent | 231 (98%) | 207 (99.5%) | 24 (89%) | <0.001 |
| Present | 4 (2%) | 1 (0.5%) | 3 (11%) | |
| Margin status (n = 234) | ||||
| Negative | 234 (100%) | 207 (100%) | 27 (100%) | NA |
| Radioactive iodine (n = 222) | ||||
| No | 163 (74%) | 147 (76%) | 16 (62%) | 0.109 |
| Yes | 56 (26%) | 46 (24%) | 10 (38%) | |
| Clinical outcome (n = 219) | ||||
| Follow-up period, years, median (range) | 5.4 (0.1–28.1) | 5.4 (0.1–28.1) | 6.4 (0.1–26) | 0.796 |
| Distant metastasis | ||||
| Absent | 216 (99%) | 190 (98%) | 26 (100%) | 0.520 |
| Present | 3 (1%) | 3 (2%) | 0 (0%) | |
| Locoregional recurrence | ||||
| Absent | 219 (100%) | 193 (100%) | 26 (100%) | NA |
p-Values are obtained by using Fisher's exact test or Chi-square test for categorical variables, and log rank test for outcome (distant metastasis-free survival). Significant p-values are highlighted in bold.
The BRAF and NRAS mutational status was determined by immunohistochemistry using monoclonal antibodies for BRAFV600E and NRASQ61R in a subset of 100 randomly selected cases.
NA, not applicable.