title: Soft tissue osteosarcoma: a case report.
abstract: Osteosarcomas arising from extraskeletal locations are extremely rare and their true prevalence is unknown. We describe a case of soft tissue-origin-osteosarcoma arising from the vastus medialis muscle in a 58-year old woman. The possibility of a malignant tumour was not suspected initially and she was referred to a specialist unit only one year after the onset of the swelling. She was successfully treated with a surgical resection, chemotherapy and radiotherapy. Because of the rarity of the tumour, a high degree of suspicion is required to make an early diagnosis. The differential diagnosis of a soft tissue mass located in the thigh in a patient over the age of 40 years, should include extraskeletal osteosarcoma.
authors.affiliation: University Department of Orthopaedics and Trauma, Manchester Royal Infirmary, United Kingdom. nhulse@yahoo.com
authors.forename: Narayan
authors.initials: N
authors.lastname: Hulse
authors.forename: Ashok S
authors.initials: AS
authors.lastname: Paul
mesh_terms: D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012516:Osteosarcoma / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy; D013848:Thigh