Table 2 Histopathological features of primary acral and non-acral melanoma.
Histopathology | Primary acral melanomas (n = 34), no. (%) | Primary non-acral melanomas (n = 10), no. (%) |
|---|---|---|
Breslow thickness | ||
Up to 1.0 mm | 2 (5.8) | 2 (20) |
1.1–2.0 mm | 11 (32.4) | 3 (30) |
2.1–4.0 mm | 8 (23.6) | 1 (10) |
>4.0 mm | 13 (38.2) | 4 (40) |
Ulceration present | 17 (50) | 2 (20) |
Mitotic rate (mitoses per mm2) | ||
<1 | 1 (2.9) | 1 (10) |
1 | 8 (23.5) | 3 (30) |
>1 | 25 (73.6) | 6 (60) |
Radial growth phase (present) | 21 (61.8) | 5 (50) |
Vertical growth phase (present) | 34 (100) | 10 (100) |
Regression (present) | 18 (52.9) | 3 (30) |
Lymphovascular invasion (present) | 6 (17.6) | 0 |
Perineural invasion (present) | 10 (29.4) | 0 |
Satellitosis (present) | 15 (44.1) | 0 |
Tumor infiltrating lymphocytes (present, non-brisk) | 34 (100) | 10 (100) |
Associated nevus (present) | 2 (5.9) | 2 (20) |
