Table 2. Histological variables and BRAF V600E mutation.
| BRAF V600E | |||||
|---|---|---|---|---|---|
| Variable | Category | negativea | positiveb | Total | P value |
| Histological subtype | S. Spreading | 19 (67.9%) | 9 (32.1%) | 28 | 1.0 |
| L. Maligna | 2 (100%) | 0 | 2 | ||
| not informed | 2 (100%) | 0 | 2 | ||
| **Growth | In situ | 17 (94.4%) | 1 (5.6%) | 18 | 0.03 |
| Radial | 3 (42.9%) | 4 (57.1%) | 7 | ||
| Vertical | 3 (42.9%) | 4 (57.1%) | 7 | ||
| Ulceration | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Clark | II | 3 (42.9%) | 4 (57.1%) | 7 | 1.0 |
| III | 3 (42.9%) | 4 (57.1%) | 7 | ||
| Breslow | Mean (SD) | 0.67 (0.23) | 0.64 (0.25) | 0.6 | |
| Mitotic Index mm2 | Mean (SD) | 0.40 (0.92) | 0.37 (0.89) | 0.6 | |
| Peritumoral Invasion | Present | 6 (46.2%) | 7 (53.8%) | 13 | 1.0 |
| Absent | 0 | 1 (100%) | 1 | ||
| Intratumoral Invasion | Present | 2 (28.6%) | 5 (71.4%) | 7 | 0.6 |
| Absent | 4 (57.1%) | 3 (42.9%) | 7 | ||
| Regression | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Lymphatic Invasion | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Vascular Invasion | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Perineural Invasion | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Previous nevus | Present | 6 (66.7%) | 3 (33.3%) | 9 | 0.7 |
| Absent | 17 (73.9) | 6 (26.1%) | 23 | ||
| Microscopic Satelitosis | Absent | 6 (42.9%) | 8 (57.1%) | 14 | + |
| Margins | Free | 20 (69.0%) | 9 (31.0%) | 29 | 0.5 |
| Positive | 3 (100%) | 0 | 3 | ||
**Fisher’s Exact Test
a. Negative: absence of staining
b. Positive: any positive staining (focal or multifocal).