Spindle-stellate cells with fascicular-storiform pattern
Abundant pale amphophilic cytoplasm
Round-ovoid nuclei with prominent small nucleoli; occasional mitotic activity
Interspersed "ganglion-like" epithelioid cells; abundant amphophilic cytoplasm; eccentric round-ovoid nuclei with prominent nucleoli and occasional bi-nucleation
Incomplete rim of metaplastic bone; mild chronic inflammatory infiltrate
Spindle-stellate cells with vague fascicular pattern
Abundant pale amphophilic cytoplasm
Round-ovoid nuclei with prominent small nucleoli; occasional mitotic activity
Myxoid-collagenous stroma; seams of osteoid with varialble mineralization; scattered osteoclast-like giant cells
RNA-seq: COL1A1::USP6 gene fusion
Fascicles of spindle-stellate cells
Pale eosinophilic cytoplasm
Ovoid euchromatic nuclei with milt atypia; mitotic activity is inconspicuous
Trabeculae of woven bone with osteoblastic rimming
Chondrocytes set within lacunae in a hyaline matrix