title: Total hip arthroplasty-related osteogenic osteosarcoma: case report and review of the literature.
abstract: BACKGROUND
  Orthopedic implant-related sarcoma is an exceedingly rare, but a known complication of total hip arthroplasty (THA).
  
  
  METHODS
  The authors describe clinical and radiologic features, histologic appearance, and treatment of osteogenic osteosarcoma located in the proximal femoral diaphysis associated with an unstable femoral prosthesis following THA in a 65-year-old male patient. The patient with HLA-B27 positive ankylosing spondylitis underwent arthroplasty 15 years ago.
  
  
  CONCLUSIONS
  The neoplastic process may be considered as an extraordinary complication of THA and might just be coincidental or the result of some derangement of the healing process in host tissue with no definitely proven hypothesis that the implants or their by-products are carcinogenic. The soluble chemical substances from the implanted prosthetic material are, at least in animals, suspected to play a vital role in the pathogenesis of the neoplastic transformation of the bone tissue. The presented case shall alert orthopedic surgeons to clinical, radiologic, and macroscopic similarities between a malignant tumor and benign lesions caused by wear debris at THA sites. At the examination of plane X-rays of patients with THA loosening, the differential diagnosis should always include osteogenic sarcoma, as well. To our knowledge, there have been only nine cases of THA-related osteogenic osteosarcomas described in the English-language literature.
authors.affiliation: Department of Pathology, University Medical Centre Maribor, Ljubljanska ulica 5, 2000, Maribor, Slovenia. rajko.kavalar@gmail.com.
authors.forename: Rajko
authors.initials: R
authors.lastname: Kavalar
authors.affiliation: Department of Orthopedics, University Medical Centre Maribor, Maribor, Slovenia. samo.fokter@guest.arnes.si.
authors.forename: Samo K
authors.initials: SK
authors.lastname: Fokter
authors.affiliation: Department of Pathology, Institute of Oncology, Ljubljana, Slovenia. jlamovec@onko-i.si.
authors.forename: Janez
authors.initials: J
authors.lastname: Lamovec
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods*; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D003937:Diagnosis, Differential; D018483:Diaphyses / Q000000981:diagnostic imaging; D005269:Femur / Q000000981:diagnostic imaging; D015796:HLA-B27 Antigen / Q000378:metabolism; D006801:Humans; D008297:Male; D012516:Osteosarcoma / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D011859:Radiography; D013167:Spondylitis, Ankylosing / Q000378:metabolism / Q000601:surgery
chemical_list: D015796:HLA-B27 Antigen