title: Influence of neuroblastoma stage on serum-based detection of MYCN amplification.
abstract: BACKGROUND
  MYCN oncogene amplification has been defined as the most important prognostic factor for neuroblastoma (NB), the most common solid extracranial neoplasm in children. High copy numbers are strongly associated with rapid tumor progression and poor outcome, independently of tumor stage or patient age, and this has become an important factor in treatment stratification.
  
  
  METHODS
  By real-time quantitative PCR analysis, we evaluated the clinical relevance of circulating MYCN DNA of 267 patients with locoregional or metastatic NB in children less than 18 months of age.
  
  
  RESULTS
  For patients in this age group with INSS stage 4 or 4S NB and stage 3 patients, serum-based determination of MYCN DNA sequences had good sensitivity (85%, 83%, and 75% respectively) and high specificity (100%) when compared to direct tumor gene determination. In contrast, the approach showed low sensitivity patients with stages 1 and 2 disease.
  
  
  CONCLUSIONS
  Our results show that the sensitivity of the serum-based MYCN DNA sequence determination depends on the stage of the disease. However, this simple, reproducible assay may represent a reasonably sensitive and very specific tool to assess tumor MYCN status in cases with stage 3 and metastatic disease for whom a wait and see strategy is often recommended.
authors.affiliation: Centre Léon Bérard, Laboratoire de Recherche Translationnelle, Lyon, France. combaret@lyon.fnclcc.fr
authors.forename: Valerie
authors.initials: V
authors.lastname: Combaret
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hogarty
authors.forename: Wendy B
authors.initials: WB
authors.lastname: London
authors.forename: Patrick
authors.initials: P
authors.lastname: McGrady
authors.forename: Isabelle
authors.initials: I
authors.lastname: Iacono
authors.forename: Stephanie
authors.initials: S
authors.lastname: Brejon
authors.forename: Katrien
authors.initials: K
authors.lastname: Swerts
authors.forename: Rosa
authors.initials: R
authors.lastname: Noguera
authors.forename: Nicole
authors.initials: N
authors.lastname: Gross
authors.forename: Raphael
authors.initials: R
authors.lastname: Rousseau
authors.forename: Alain
authors.initials: A
authors.lastname: Puisieux
mesh_terms: D002648:Child; D004273:DNA, Neoplasm / Q000097:blood*; D005784:Gene Amplification; D016259:Genes, myc; D006801:Humans; D009367:Neoplasm Staging; D009447:Neuroblastoma / Q000235:genetics* / Q000473:pathology; D012189:Retrospective Studies
chemical_list: D004273:DNA, Neoplasm