Hemangiopericytoma.
D000293:Adolescent; D000328:Adult; D000368:Aged; D005121:Extremities; D005260:Female; D006258:Head and Neck Neoplasms / Q000601:surgery; D006393:Hemangiopericytoma / Q000401:mortality / Q000532:radiotherapy / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D010534:Peritoneal Neoplasms / Q000601:surgery; D012189:Retrospective Studies