title: BRAF analysis by fine needle aspiration biopsy of thyroid nodules improves preoperative identification of papillary thyroid carcinoma and represents a prognostic factor. A mono-institutional experience.
abstract: BACKGROUND
  The current preoperative diagnosis of a thyroid mass relies on microscopic evaluation of thyroid cells obtained by fine needle aspiration biopsy (FNAB). More recently, FNAB has been combined with molecular analysis to increase the accuracy of the cytological evaluation. In this mono-institutional prospective study, we evaluated whether the routine introduction of BRAF testing in thyroid FNAB could help ameliorate the preoperative recognition of papillary thyroid carcinoma (PTC) in "suspended" or malignant cytological categories. Moreover, we investigated the prognostic role of the BRAFV600E mutation in PTC.
  
  
  METHODS
  BRAFV600E analysis was performed in thyroid FNAB from 270 patients classified into one of five cytological categories THY1, THY2, THY3, THY4, THY5. All subsequently underwent thyroidectomy±node dissection, from October 2008 to September 2009 in our Department. For each cytological category, we considered the definitive histological diagnosis of PTC and the presence of the BRAFV600E mutation. In 141 patients with a final tissue diagnosis of PTC, we correlated the presence of BRAFV600E with gender, age, histotype, TNM, size of the lesion, extracapsular extension, node metastases and multifocality.
  
  
  RESULTS
  The prevalence of the BRAFV600E mutation, among PTCs at final tissue diagnosis, was 69%. It improved the FNAB diagnostic accuracy from 88% to 91%. The BRAFV600E mutation was correlated with older age, classical variant of PTC, advanced stages in patients > 45 years.
  
  
  CONCLUSIONS
  BRAFV600E testing could play a role in improving the diagnostic accuracy of FNAB for PTC, representing a useful adjuvant tool in presurgical characterization of thyroid nodes in particular cases. There is an association between the BRAFV600E mutation and some clinico-pathological characteristics of PTC.
authors.affiliation: Department of Surgical Pathology, Institution of Medical and Surgical Sciences, University Hospital of Padova, Padova, Italy.
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Pelizzo
authors.forename: Isabella Merante
authors.initials: IM
authors.lastname: Boschin
authors.forename: Susi
authors.initials: S
authors.lastname: Barollo
authors.forename: Gianmaria
authors.initials: G
authors.lastname: Pennelli
authors.forename: Antonio
authors.initials: A
authors.lastname: Toniato
authors.forename: Laura
authors.initials: L
authors.lastname: Zambonin
authors.forename: Federica
authors.initials: F
authors.lastname: Vianello
authors.forename: Andrea
authors.initials: A
authors.lastname: Piotto
authors.forename: Eric Casal
authors.initials: EC
authors.lastname: Ide
authors.forename: Costantino
authors.initials: C
authors.lastname: Pagetta
authors.forename: Nadia
authors.initials: N
authors.lastname: Sorgato
authors.forename: Francesca
authors.initials: F
authors.lastname: Torresan
authors.forename: Maria Elisa
authors.initials: ME
authors.lastname: Girelli
authors.forename: Davide
authors.initials: D
authors.lastname: Nacamulli
authors.forename: Franco
authors.initials: F
authors.lastname: Mantero
authors.forename: Caterina
authors.initials: C
authors.lastname: Mian
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D002277:Carcinoma; D002291:Carcinoma, Papillary; D002648:Child; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D057234:Preoperative Period; D011379:Prognosis; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D025321:Surgery, Computer-Assisted; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000473:pathology / Q000601:surgery; D016606:Thyroid Nodule / Q000000981:diagnostic imaging / Q000235:genetics* / Q000473:pathology*; D014463:Ultrasonography; D055815:Young Adult
chemical_list: C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf