TABLE 2.
Histologic features of intracranial mesenchymal tumors with FET‐CREB fusions
| Histologic feature | All tumors | EWSR1‐ATF1 | EWSR1‐CREB1 | EWSR1‐CREM | FUS‐CREM | |
|---|---|---|---|---|---|---|
| Mucin‐rich stromaa | 12/20 (60%) | 3/8 (38%) | 7/7 (100%) | 2/4 (50%) | 0/1 (0%) | p = 0.03 |
| Collageneous stroma ‐ intercellular matrix | 20/20 (100%) | 8/8 (100%) | 7/7 (100%) | 4/4(100%) | 1/1 (100%) | |
| Collagenous stroma ‐ internodular septae | 14/20 (70%) | 4/8 (50%) | 6/7 (86%) | 3/4 (75%) | 1/1 (100%) | |
| Epithelioid/rhabdoid morphologya | 10/20 (50%) | 7/8 (88%) | 1/7 (14%) | 1/4 (25%) | 1/1 (100%) | p = 0.01 |
| Stellate/spindle cell morphologya | 10/20 (50%) | 1/8 (13%) | 7/7 (100%) | 2/4 (50%) | 0/1 (0%) | p = 0.001 |
| Round cell morphology | 2/20 (10%) | 1/8 (13%) | 0/7 (0%) | 1/4 (25%) | 0/1 (0%) | |
| Hemangioma‐like vasculaturea | 10/20 (50%) | 2/8 (25%) | 6/7 (86%) | 2/4 (50%) | 0/1 (0%) | p = 0.04 |
| Staghorn/HPC‐like vasculature | 4/20 (20%) | 1/8 (13%) | 1/7 (14%) | 2/4 (50%) | 0/1 (0%) | |
| Pseudoangiomatoid vasculature | 0/20 (0%) | 0/8 (0%) | 0/7 (0%) | 0/4 (0%) | 0/1 (0%) | |
| Dense lymphoplasmacytic cuffing | 12/20 (60%) | 4/8 (50%) | 6/7 (86%) | 1/4 (25%) | 1/1 (100%) | |
| Hemosiderin/hematoidin | 13/20 (65%) | 3/8 (38%) | 6/7 (86%) | 3/4 (75%) | 1/1 (100%) | |
| Meningioma‐like whorls | 4/20 (20%) | 3/8 (38%) | 0/7 (0%) | 1/4 (25%) | 0/1 (0%) | |
| Amianthoid fibers | 2/20 (10%) | 1/8 (13%) | 1/7 (14%) | 0/4 (0%) | 0/1 (0%) | |
| Necrosis | 2/20 (10%) | 1/8 (13%) | 0/7 (0%) | 1/4 (25%) | 0/1 (0%) |
a
Denotes histologic features which are (bold values) statistically significantly different (p < 0.05) when comparing tumors with EWSR1‐ATF1 fusion versus EWSR1‐CREB1 fusion via unpaired, non‐parametric t‐test (Mann‐Whitney).