title: Parameningeal rhabdomyosarcoma in pediatric age: results of a pooled analysis from North American and European cooperative groups.
abstract: BACKGROUND
  Parameningeal (PM) site is a well-known adverse prognostic factor in children with localized rhabdomyosarcoma (RMS). To identify risk factors associated with outcome at this site, we pooled data from 1105 patients treated in 10 studies conducted by European and North American cooperative groups between 1984 and 2004.
  
  
  METHODS
  Clinical factors including age, histology, size, invasiveness, nodal involvement, Intergroup Rhabdomyosarcoma Study (IRS) clinical group, site, risk factors for meningeal involvement (MI), study group, and application of radiotherapy (RT) were studied for their impact on event-free and overall survival (EFS and OS).
  
  
  RESULTS
  Ten-year EFS and OS were 62.6 and 66.1% for the whole group. Patients without initial RT showed worse survival (10-year OS 40.8% versus 68.5% for RT treated patients). Multivariate analysis focusing on 862 patients who received RT as part of their initial treatment revealed four unfavorable prognostic factors: age <3 or >10 years, signs of MI, unfavorable site, and tumor size. Utilizing these prognostic factors, patients could be classified into different risk groups with 10-year OS ranging between 51.1 and 80.9%.
  
  
  CONCLUSIONS
  While, in general, PM localization is regarded as an adverse prognostic factor, the current analysis differentiates those with good prognosis (36% patients with 0-1 risk factor: 10-year OS 80.9%) from high-risk PM patients (28% with 3-4 factors: 10-year OS 51.1%). Furthermore, this analysis reinforces the necessity for RT in PM RMS.
authors.affiliation: Department of Pediatric Oncology, Emma Children's Hospital-Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: J H M
authors.initials: JH
authors.lastname: Merks
authors.forename: G L
authors.initials: GL
authors.lastname: De Salvo
authors.forename: C
authors.initials: C
authors.lastname: Bergeron
authors.forename: G
authors.initials: G
authors.lastname: Bisogno
authors.forename: A
authors.initials: A
authors.lastname: De Paoli
authors.forename: A
authors.initials: A
authors.lastname: Ferrari
authors.forename: A
authors.initials: A
authors.lastname: Rey
authors.forename: O
authors.initials: O
authors.lastname: Oberlin
authors.forename: M C G
authors.initials: MC
authors.lastname: Stevens
authors.forename: A
authors.initials: A
authors.lastname: Kelsey
authors.forename: J
authors.initials: J
authors.lastname: Michalski
authors.forename: D S
authors.initials: DS
authors.lastname: Hawkins
authors.forename: J R
authors.initials: JR
authors.lastname: Anderson
mesh_terms: D016543:Central Nervous System Neoplasms / Q000401:mortality* / Q000532:radiotherapy; D003131:Combined Modality Therapy; D006801:Humans; D053208:Kaplan-Meier Estimate; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012208:Rhabdomyosarcoma / Q000401:mortality* / Q000532:radiotherapy
keywords: meningeal involvement; parameningeal; radiotherapy; rhabdomyosarcoma