Table 1.
Malignant epithelioid neoplasm harboring EWSR1/FUS-CREB fusions
| Case # | Age/Sex | Fusion | Site/Size | Morphology | Positive IHC | FU |
|---|---|---|---|---|---|---|
| 1 | 54/F | FUS-CREM | mesocolon mass (14.5 cm) | Epithelioid, rhabdoid, cystic, lymphoid cuff, calcifications, focal necrosis | AE1/3, EMA, WT1, desmin (focal), CD99 (weak) | |
| 2 | 10/F | FUS-CREM | rectovaginal pouch (4 cm) | Epithelioid, cystic, lymphoid cuff | AE1/3, Cam 5.2, EMA, Inhibin, WT1, desmin (focal), CD99 (weak) | LR x2 (11 & 18 mo), peritoneal nodules s/p chemotherapy (cisplatin, etoposide, bleomycin); NED 4 years |
| 3 | 63M | FUS-CREM* | omental mass (2.0 cm) |
Epithelioid, rhabdoid, cystic, lymphoid cuff | AE1/3, Cam5.2, EMA, WT1 | |
| 4 | 9/M | EWSR1-CREM | adrenal mass (3.5 cm) | Epithelioid, tubular structures, cystic, lymphoid cuff, calcifications | AE1/3, Cam5.2, EMA (focal), WT1 (focal), inhibin, desmin (focal), CD99 (weak) | NED, 31 mo |
| 5 | 47/F | EWSR1-CREM* | mesocolic (9 cm) | Epithelioid & spindle, cystic, lymphoid cuff | CK (focal) | peritoneal mets |
| 6 | 25/M | EWSR1-CREM | intra-abdominal, inseparable from gastric fundus (7 cm) | Epithelioid & round, cystic, lymphoid cuff | EMA (focal), WT1 (rare) | liver mets |
| 7 | 53/M | FUS-CREM* | forearm mass with bone erosion (15 cm) | Epithelioid, cystic, lymphoid cuff | none | |
| 8 | 44/F | EWSR1-CREM* | pleura (10 cm) | Epithelioid & round, rhabdoid, cystic, pseudopapillary | AE1/3 (focal); EMA, inhibin (focal) | LR & LN mets, s/p neoadjuvant chemotherapy & extrapleural pneumonectomy, AWD 4 mo |
| 9 | 62/M | EWSR1-ATF1* | peri-pancreatic mass (5.3 x 3.7 x 4.5) | Epithelioid & spindle, cystic, lymphoid cuff; moderate atypia | EMA (focal), ALK | NED 9 mo |
| 10 | 20/F | EWSR1-CREM* | peri-rectal (9 cm) | Epithelioid & spindle, myxoid | CK (focal), EMA (focal) | LRx3, NED, 17 years |
| 11 | 14/F | EWSR1-CREM* | thigh (4.5 x 3 cm) | Epithelioid, rhabdoid, cystic | CK (focal), EMA (focal), CD99 | |
| 12 | 29/M | EWSR1-CREM* | kidney (10 cm) | Round & epithelioid, cystic | CK (focal) | peritoneal & para-aortic mets |
| 13 | 36/F | EWSR1-ATF1* | rectovaginal pouch | Epithelioid, rhabdoid, cystic, lymphoid cuff | AE1/3, Cam5.2, EMA EM: tonofilaments | peritoneal LR s/p chemo |
*
RNA sequencing; mets, metastases; LR, local recurrence; mo, months; EM, electron microscopy.