title: Effect of timing of pulmonary metastases identification on prognosis of patients with osteosarcoma: the Japanese Musculoskeletal Oncology Group study.
abstract: OBJECTIVE
  The prognostic value of the time of identification of lung metastasis was investigated in 280 patients with metastatic lung osteosarcoma as a multi-institutional study of the Japanese Musculoskeletal Oncology Group.
  
  
  METHODS
  The 280 patients with lung metastasis were divided into four groups: group 1, patients with lung metastasis identified at initial presentation; group 2, those with lung metastasis identified during preoperative chemotherapy; group 3, those with lung metastasis identified during postoperative chemotherapy, and group 4, those with lung metastasis identified after completion of treatment. Survivals of the four groups were compared. Additionally, the effects of number of metastatic nodules, metastasectomy, and the effect of chemotherapy on the primary tumor on survival of the four groups were analyzed.
  
  
  RESULTS
  There were 46 patients in group 1, 30 in group 2, 94 in group 3, and 110 in group 4. The overall 2-year survival rates from the time of identification of lung metastasis were 33%, 31%, 24%, and 40% for groups 1, 2, 3, and 4, respectively, whereas the 5-year survival rates were 18%, 0%, 6%, and 31%, respectively. Patients in group 4 thus demonstrated significantly better prognosis than any of the other patients (P <.0001).
  
  
  CONCLUSIONS
  Time of identification of lung metastasis is an important prognostic factor. In terms of clinical behavior, groups 2 and 3 are completely different than group 4. These data ensure the need to stratify stage III osteosarcomas into subgroups according to the time of diagnosis of lung metastases. To improve the survival of osteosarcoma patients, new treatment modalities should be introduced into the treatment armamentarium for lung metastasis from osteosarcoma, especially in groups 1, 2, and 3.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-8641, Japan. tsuchi@med.kanazawa-u.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsuchiya
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Kanazawa
authors.forename: Mohamed E
authors.initials: ME
authors.lastname: Abdel-Wanis
authors.forename: Naohiro
authors.initials: N
authors.lastname: Asada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Abe
authors.forename: Kazuo
authors.initials: K
authors.lastname: Isu
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugita
authors.forename: Katsuro
authors.initials: K
authors.lastname: Tomita
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003657:Decision Making; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology* / Q000556:secondary* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012516:Osteosarcoma / Q000401:mortality / Q000473:pathology* / Q000556:secondary* / Q000628:therapy; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors