Fig. 3

Invasive tumor composed of spindle and epitheloid tumor cells. The tumor invaded muscularis propia (a, 4x; b, 20x). The majority of tumor was comprised of bland spindle cells embedded in myxoid stroma (c, 4x; d, 20x). There were areas comprised of epitheloid tumor cells forming cord-like architecture (e, 10x) and with prominent atypia (f, 40x). There was also focal collagen rosette (g, 4x), and epitheloid cell whorls (h-j) with prominent atypia and rare nuclear inclusion (j). h, 10x; i & j, 40x). Focal osseous metaplasia (k, post decalcification, 4x) and focal perivascular condensation of bland spindle cells (l, 10x) were also present