title: FGF10 Signaling differences between type I pleuropulmonary blastoma and congenital cystic adenomatoid malformation.
abstract: BACKGROUND
  Type I pleuropulmonary blastoma (PPB) and congenital cystic adenomatoid malformation of the lung (CCAM) are cystic lung diseases of childhood. Their clinical and radiological presentations are often similar, and pathologic discrimination remains difficult in many cases. As a consequence, type I PPB and CCAM are frequently confused, leading to delayed adequate management for type I PPB. Recent studies have suggested a role for fibroblast growth factor (FGF) 10 signal pathway in CCAM pathogenesis. The objective of our study was to determine whether FGF10 signaling differs between CCAM and type I PPB.
  
  
  METHODS
  Immunohistochemical studies were performed for expression of FGF10, its receptor FGFR2b, and its inhibitor sonic hedgehog (SHH) in focal type I PPB (n=6), CCAM type I (n=7), CCAM type II (n=7), and control lungs (n=5).
  
  
  RESULTS
  FGF10, FGFR2b, and SHH expressions differed markedly between type I PPB and both types of CCAM. Type I and type II CCAM cystic walls expressed FGF10, FGFR2b, and SHH, whereas staining was absent or poor in type I PBB cystic walls. Expression of FGF10, FGFR2b, and SHH did not differ between CCAM cystic walls and control airway walls.
  
  
  CONCLUSIONS
  These findings show that immunohistochemistry with FGF10, FGFR2b, or SHH could be useful in differentiating CCAM from type I PPB, when a child presents with a focal cystic lung lesion. The absence of strong expression of FGF10, FGFR2b, and/or SHH makes the diagnosis of CCAM very doubtful.
authors.affiliation: AP-HP, Hôpital Necker-Enfants Malades, service de Pneumologie Pédiatrique, Centre de Référence pour les Maladies Respiratoires Rares de l'Enfant, Paris, France. christophe.delacourt@nck.aphp.fr.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Lezmi
authors.forename: Virginie
authors.initials: V
authors.lastname: Verkarre
authors.forename: Naziha
authors.initials: N
authors.lastname: Khen-Dunlop
authors.forename: Shamila
authors.initials: S
authors.lastname: Vibhushan
authors.forename: Alice
authors.initials: A
authors.lastname: Hadchouel
authors.forename: Caroline
authors.initials: C
authors.lastname: Rambaud
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Copin
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Rittie
authors.forename: Alexandra
authors.initials: A
authors.lastname: Benachi
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Fournet
authors.forename: Christophe
authors.initials: C
authors.lastname: Delacourt
mesh_terms: D015615:Cystic Adenomatoid Malformation of Lung, Congenital / Q000235:genetics / Q000378:metabolism*; D005260:Female; D051526:Fibroblast Growth Factor 10 / Q000235:genetics / Q000378:metabolism*; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018202:Pulmonary Blastoma / Q000235:genetics / Q000378:metabolism*; D051497:Receptor, Fibroblast Growth Factor, Type 2 / Q000235:genetics / Q000378:metabolism*
chemical_list: C496463:FGF10 protein, human; D051526:Fibroblast Growth Factor 10; D053823:Hedgehog Proteins; C509239:SHH protein, human; D051497:Receptor, Fibroblast Growth Factor, Type 2