title: Prognostic relevance of KIT and PDGFRA mutations in gastrointestinal stromal tumors.
abstract: BACKGROUND
  Prediction of biological behavior is crucial for selection of new therapeutic modalities in GIST. Here, we aimed to assess whether KIT and PDGFRA mutations have survival impact in gastrointestinal stromal tumors (GIST).
  
  
  METHODS
  Fifty-five Brazilian patients with completely resected GIST were examined for KIT and PDGFRA mutations. The 5-year disease-free survival (DFS) was analyzed.
  
  
  RESULTS
  KIT and PDGFRA mutations were identified in 74.5% and 7.3% of patients, respectively. The 5-year DFS rate for all patients was 52.8%. The 5-year DFS rate was lower in patients with tumors having in-frame deletions or concomitant in-frame deletions and insertions affecting codons 557-558 than in patients with tumors having other exon 11 KIT mutations (p=0.023). Conversely, when the patients with concomitant deletion-insertion mutations affecting codons 557-558 were excluded from the analysis, deletions involving codons 557-558 had no influence on 5-year DFS rates.
  
  
  CONCLUSIONS
  Our findings indicate that a specific KIT mutation may be associated with unfavorable behavior in GIST. This finding may have implications on selecting patients for adjuvant therapy.
authors.affiliation: Center of Bone Marrow Transplantation (CEMO), Instituto Nacional de Câncer (INCA), Rio de Janeiro, Brazil.
authors.forename: Esteban
authors.initials: E
authors.lastname: Braggio
authors.forename: Danielle De Almeida
authors.initials: Dde A
authors.lastname: Braggio
authors.forename: Isabele Avila
authors.initials: IA
authors.lastname: Small
authors.forename: Lisandro F
authors.initials: LF
authors.lastname: Lopes
authors.forename: Marcus
authors.initials: M
authors.lastname: Valadão
authors.forename: Maria Emmerick
authors.initials: ME
authors.lastname: Gouveia
authors.forename: Aline Dos Santos
authors.initials: Ados S
authors.lastname: Moreira
authors.forename: Eduardo
authors.initials: E
authors.lastname: Linhares
authors.forename: Sérgio
authors.initials: S
authors.lastname: Romano
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Bacchi
authors.forename: Ilana Zalcberg
authors.initials: IZ
authors.lastname: Renault
authors.forename: Denise Peixoto
authors.initials: DP
authors.lastname: Guimarães
authors.forename: Carlos Gil
authors.initials: CG
authors.lastname: Ferreira
mesh_terms: D000328:Adult; D000368:Aged; D003062:Codon; D005091:Exons; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics*
chemical_list: D003062:Codon; D019009:Proto-Oncogene Proteins c-kit; D020796:Receptor, Platelet-Derived Growth Factor alpha