title: Primary Metastatic Synovial Sarcoma: Experience of the CWS Study Group.
abstract: Prognostic factors for localized synovial sarcoma are well defined. However, few data exist regarding patients with metastases at diagnosis. Poor outcome is described but the optimal therapeutic regimen remains unclear. Our aim was to assess the outcome, identify prognostic factors, and analyze treatment strategies.
  
  
  
  Patients <21 years with synovial sarcoma and primary distant metastases treated in the consecutive prospective European Cooperative Weichteilsarkom Studiengruppe trials 1980-2010 were analyzed.
  
  
  
  Twenty-nine of 296 patients had primary metastases. Twenty-seven could be included. Median age was 16.7 years. Primaries were mainly located in the limbs (78%) and 74% were ≥10 cm. Metastases involved the lungs in all patients. Two patients presented with synchronous bone metastases. Sixty-three percent of patients achieved a first remission, whereas only 26% maintained it. Relapses were metastatic with pulmonary metastases in nearly all patients. Five-year event-free survival and overall survival (OS) rates were 26% and 30%, respectively. Prognosis was best for patients with oligometastatic lung metastases (5-year OS probability 85%). Prognosis was worse for patients with multiple bilateral lung metastases (5-year OS 13%) and even poorer for those with concurrent bone metastases. Treatment elements associated with superior survival were adequate local therapy of the primary tumor and, if feasible, for metastases, chemotherapy with an ifosfamide/doxorubicin-based regimen. The use of whole lung irradiation was not correlated with better outcomes.
  
  
  
  The overall prognosis of primary metastatic synovial sarcoma is poor. However, individuals with oligometastatic lung metastases had very good chance for long-term survival when treated with adequate multimodal therapy.
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Scheer
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Dantonello
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.
authors.forename: Erika
authors.initials: E
authors.lastname: Hallmen
authors.affiliation: Department of Pediatric Pathology, Kiel Pediatric Tumor Registry, University Hospital of Schleswig-Holstein, Campus Kiel, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Vokuhl
authors.affiliation: Department of Pediatric Pathology, Kiel Pediatric Tumor Registry, University Hospital of Schleswig-Holstein, Campus Kiel, Germany.
authors.forename: Ivo
authors.initials: I
authors.lastname: Leuschner
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Sparber-Sauer
authors.affiliation: Department of Pediatric Hematology/Oncology and BMT, University of Wroclaw, Wroclaw, Poland.
authors.forename: Bernarda
authors.initials: B
authors.lastname: Kazanowska
authors.affiliation: Department of Pediatric Oncology, University of Zurich, Zurich, Switzerland.
authors.forename: Felix
authors.initials: F
authors.lastname: Niggli
authors.affiliation: St. Anna Kinderspital and St. Anna Kinderkrebsforschung e.V, Vienna, Austria.
authors.forename: Ruth
authors.initials: R
authors.lastname: Ladenstein
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.|Department of Pediatric Hematology and Oncology, University Children's Hospital Muenster, Münster, Germany.
authors.forename: Stefan S
authors.initials: SS
authors.lastname: Bielack
authors.affiliation: Hospital for Children and Adolescents, Goethe-University Frankfurt, Frankfurt am Main, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Klingebiel
authors.affiliation: Pediatrics 5, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany.|Department of Pediatric Oncology, University of Tuebingen, Tuebingen, Germany.
authors.forename: Ewa
authors.initials: E
authors.lastname: Koscielniak
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000556:secondary*; D008297:Male; D009362:Neoplasm Metastasis; D011446:Prospective Studies; D013584:Sarcoma, Synovial / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate
keywords: metastatic sarcoma; oligometastatic; oligometastatic sarcoma; pediatric sarcoma; soft tissue sarcoma; synovial sarcoma