Cords of round-epithelioid cells.
Amphophilic cytoplasm
Round-ovoid nuclei with small nucleoli; milt pleomorphism; mitotic activity
Trabeculae of dense woven bone
IHC: keratin AE1/AE3, SATB2
RNA-seq: EWSR1::SSX3 gene fusion
PMID: 38050902; 33987888; 34538011
Sheets, cords and chains of epithelioid cells
Pale amphophilic-clear cytoplasm
Round-ovoid nuclei with mild atypia; inconspicuous mitotic activity
Abundant myxo-hyaline stroma
IHC: keratin (AE1/AE3). epithelial membrane antigen
RNA-seq: EWSR1::NFATC2 gene fusion
PMID: 30895378
Fascicles of spindle cells with admixed nests of round cells
Pale amphophilic cytoplasm
Round-ovoid hyperchromatic nuclei with mild pleomorphism and occasional binucleation; mitotic activity
Myxoid stroma with occasional thick collagen bundles
RNA-seq: EWSR1::TFCP2 gene fusion
PMID: 32556562