title: Periosteal osteoblastoma: a case report and a review of the literature.
abstract: Osteoblastomas located on the surface of cortical bone, so-called periosteal (juxtacortical) osteoblastomas, are extremely rare. A 24-year-old man complained of pain and swelling in the left knee. The clinical and radiological investigation showed a tumor located in the posterior portion of the distal shaft of the femur. The radiological differential diagnosis included parosteal osteosarcoma, periosteal chondroma and periostitis ossificans. A frozen section was obtained and histology revealed an osteoblastoma with large epithelioid-appearing osteoblasts consistent with an aggressive osteoblastoma. An en bloc resection of the tumor was performed and the definitive histology of the whole specimen revealed a typical osteoblastoma. The authors draw attention to the fact that periosteal osteoblastoma is a rare tumor that could be mistaken clinically and histologically for other and more common tumors at this location.
authors.affiliation: Clinical Institute of Clinical Pathology, University of Vienna Medical School, Vienna, Austria. irene.sulzbacher@akh-wien.ac.at
authors.forename: I
authors.initials: I
authors.lastname: Sulzbacher
authors.forename: S
authors.initials: S
authors.lastname: Puig
authors.forename: K
authors.initials: K
authors.lastname: Trieb
authors.forename: S
authors.initials: S
authors.lastname: Lang
mesh_terms: D000328:Adult; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D003937:Diagnosis, Differential; D005269:Femur / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D018215:Osteoblastoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D010006:Osteoblasts / Q000473:pathology; D010521:Periosteum / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome