title: [Survival analysis and the effects of prognostic factors in patients treated for osteosarcoma].
abstract: OBJECTIVE
  We evaluated long-term treatment results of patients with primary osteosarcoma and the effect of prognostic factors on overall survival and disease-free survival.
  
  
  METHODS
  Between 1995 and 2005, 180 patients (111 males, 69 females; mean age 21+/-10 years; range 7 to 64 years) were treated for primary osteosarcoma. Overall and disease-free survival rates were analyzed for 165 patients with high-grade osteosarcoma with the Kaplan-Meier method. The effects of potential prognostic factors were assessed, including age, gender, localization, tumor size, primary metastasis on presentation, the presence of pathologic fractures, necrosis rate, and infection. All the patients received chemotherapy before and after surgery. The mean follow-up period was 49.7 months (range 6 to 185) months.
  
  
  RESULTS
  Sixty-nine patients were below 16 years of age. The most frequent involvement was in the distal femur (47.2%), followed by the proximal tibia (25%). Sixteen patients presented with a pathologic fracture, and 12 patients with metastasis. The median tumor size was 10 cm. The overall five- and 10-year survival rates were 68% and 60%, and disease-free survival rates were 50% and 44%, respectively. Only the presence of a pathologic fracture and primary metastasis on presentation were found to affect prognosis.
  
  
  CONCLUSIONS
  The two conditions, primary metastasis and a pathologic fracture, found as the most important prognostic factors in our study are mainly associated with late presentation. As in every malignant disease, early admission would provide better survival rates.
authors: Istanbul Universitesi Istanbul Tip Fakültesi, Ortopedi ve Travmatoloji Anabilim Dali.
authors: Harzem
authors: H
authors: Ozger
authors: Levent
authors: L
authors: Eralp
authors: Ata Can
authors: AC
authors: Atalar
authors: Berkin
authors: B
authors: Toker
authors: Inci
authors: I
authors: Ayan
authors: Rejin
authors: R
authors: Kebudi
authors: Sevil
authors: S
authors: Bağbek
authors: Mert
authors: M
authors: Başaran
authors: Fulya
authors: F
authors: Ağaoğlu
authors: Yavuz
authors: Y
authors: Dizdar
authors: Bilge
authors: B
authors: Bilgiç
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D012516:Osteosarcoma / Q000000981:diagnostic imaging / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D011379:Prognosis; D011859:Radiography; D016019:Survival Analysis; D014421:Turkey / Q000453:epidemiology