Table 1 Clinical, pathologic and molecular findings in 58 lesions.
FTS | DF | MF | |
|---|---|---|---|
Number of cases (%) | 28 | 23 | 7 |
Age, median; range (years) | 44; 5–75 | 55; 42–79 | 49; 10–56 |
Sex | |||
Male | 19 (68) | 12 (52) | 6 (86) |
Female | 9 (32) | 11 (48) | 1 (14) |
Maximum diameter, median; range (mm) | 15; 6–50 | 23; 12–60 | 12; 8–22 |
Location | |||
Fingers | 16 | 9 | 5 |
Hand/wrist | 11 | 4 | 1 |
Forearm | 0 | 1 | 0 |
Toes | 0 | 2 | 1 |
Foot/ankle | 1 | 6 | 0 |
Unspecified | 1 | ||
Lobulation | |||
Single nodule | 7 (25) | 19 (83) | 1 (14) |
Multilobulated | 21 (75) | 4 (17) | 6 (86) |
Circumscription | |||
Well defined | 8 (29) | 16 (70) | 2 (29) |
At least focally ill-defined | 20 (71) | 7 (30) | 5 (71) |
Slit-like vessels at the periphery | 28 (100) | 4 (17) | 7 (100) |
Branching vessels | 2 (7) | 0 | 5 (71) |
Keloid-like fibers | 12 (43) | 2 (9) | 0 |
Osteoclast-like giant cells | 2 (7) | 0 | 5 (71) |
Cellularity (% of the lesion, mean; range) | |||
Hypocellular sclerotic/low | 73; 10–100 | 100; 95–100 | 37; 10–80 |
Medium/high | 27; 0–90 | 0; 0–5 | 63; 20–90 |
Mitoses per 10 high power fields (mean; range) | 0.3; 0–3 | 0; 0–0 | 2.3; 0–6 |
USP6 fusion (number of positive/tested cases) | 17/18 | 0/5 | 0/4 |
PDGFRB hotpot mutation | NP | NP | 3/7 |
FOSL1 (immunohistochemistry) | 1/27 (1+) | 17/22 (15: 4+; 2:3+) | 3/7 (1+) |
CD34 | 1/12 (focally) | 1/6 (focally) | 0/7 |
SMA | 14/14 (13 diffusely, 1 multifocally) | 6/6 (3 focally, 3 multifocally) | 7/7 (5 diffusely, 2 focally) |
Desmin | 1/14 (focally) | 0/6 | 0/7 |
H-caldesmon | 0/6 | 0/4 | 0/7 |
Cytokeratin AE1AE3 | 0/6 | 0/4 | 0/7 |
S100 protein | 0/9 | 0/4 | 0/7 |
Beta-catenin (nuclear) | 0/7 | 0/4 | 0/7 |
