title: The threat of misdiagnosis of primary osteosarcoma over the age of 60: a series of seven cases and review of the literature.
abstract: BACKGROUND
  Osteosarcoma is the most common, non-haematopoietic, primary malignant bone tumour with an incidence of 0.3-0.5 per 100,000. There is some discrepancy in literature concerning the peaks of incidence of osteosarcoma. Some describe only one peak which arises in adolescence, whilst others report a bimodal age distribution with a second peak over the age of 60. In this retrospective study, we evaluated osteosarcoma patients over age 60 treated at our department and reviewed previous studies from the literature.
  
  
  METHODS
  Sixty-four patients (40 male, 24 female) with a mean age of 29 years (from 7 to 82) were treated for primary osteosarcomas. At the time of diagnosis, seven patients (two male and five female) were over 60 years of age with a mean follow-up of 46 months after definite diagnosis.
  
  
  RESULTS
  Three out of seven osteosarcomas were primarily radiologically or histologically misdiagnosed, but only one was mistreated with intramedullary nailing at a trauma centre. At last follow-up, two patients had died from the disease, three were alive with disease, and two had no evidence of osteosarcoma.
  
  
  CONCLUSIONS
  We did not find an increased incidence of primary osteosarcoma in the elderly; yet, older patients had a higher rate of misdiagnosis due to untypical radiological findings in combination with longer times from the onset of first symptoms to definite diagnosis. In cases of pathological fracture, it is essential to assess whether it is caused by mechanical stress or a primary or secondary tumour before leading into mistreatment, especially in older patients.
authors: University Clinic of Orthopaedic Surgery, Medical University of Graz, Auenbruggerplatz 5-7, Graz, Austria. patrick.sadoghi@med.uni-muenchen.de
authors: Patrick
authors: P
authors: Sadoghi
authors: Andreas
authors: A
authors: Leithner
authors: Heimo
authors: H
authors: Clar
authors: Mathias
authors: M
authors: Glehr
authors: Christine
authors: C
authors: Wibmer
authors: Koppany
authors: K
authors: Bodo
authors: Franz
authors: F
authors: Quehenberger
authors: Reinhard
authors: R
authors: Windhager
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000175:diagnosis*; D002648:Child; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012516:Osteosarcoma / Q000175:diagnosis*; D012189:Retrospective Studies; D055815:Young Adult