title: Extra-skeletal osteosarcoma presenting as a peri-ampullary mass.
authors.affiliation: University of Pittsburgh School of Medicine, Office of Medical Education, 3550 Terrace St, M211 Scaife Hall, Pittsburgh, PA, 15261, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Khalaf
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Heller
mesh_terms: D000368:Aged; D014670:Ampulla of Vater / Q000473:pathology* / Q000601:surgery; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000601:surgery; D003138:Common Bile Duct Neoplasms / Q000175:diagnosis* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D012516:Osteosarcoma / Q000175:diagnosis* / Q000601:surgery; D011379:Prognosis