In field of prior radiotherapy for prostate carcinoma
Spindle-epithelioid cells with vague fascicular pattern
Pale amphophilic cytoplasm
Round-ovoid nuclei with moderate-marked pleomorphism; conspicuous activity
Broad bands of osteoid with focal mineralization
IHC: SATB2, H3K27me3
In field of prior radiotherapy for nasopharyngeal carcinoma
Lobulated; spindle-epithelioid cell fascicles
Eosinophilic cytoplasm
Ovoid nuclei with prominent nucleoli and moderate-marked pleomorphism; conspicuous mitotic activity
Broad areas of osteoid with focal mineralization
In field of prior radiotherapy
Spindle-epithelioid cells with fascicular-herringbone pattern
Amphophilic cytoplasm
Round-ovoid nuclei with mild-moderate pleomorphism; conspicuous activity
Delicate seams of osteoid lacking mineralization; patchy necrosis
In field of prior radiotherapy
Spindle-epithelioid cells with patternless distribution
Pale amphophilic cytoplasm
Round-ovoid nuclei with mild-moderate pleomorphism; occasional activity
Broad bands of osteoid with focal mineralization
IHC: SATB2
In field of prior radiotherapy
Spindle-epithelioid cells with vague fascicular pattern
Pale amphophilic cytoplasm
Round-ovoid nuclei with moderate-marked pleomorphism; conspicuous activity
Broad bands of osteoid with focal mineralization