title: Reduction of false-negative papillary thyroid carcinomas by the routine analysis of BRAF(T1799A) mutation on fine-needle aspiration biopsy specimens: a prospective study of 814 thyroid FNAB patients.
abstract: OBJECTIVE
  To evaluate prospectively the usefulness of the routine determination of BRAF(T1799A) mutation on thyroid fine-needle aspiration biopsy (FNAB) to detect cytopathology false negative papillary thyroid carcinomas (PTC) and, therefore, as a tool to improve the sensitivity of the preoperative cytopathological diagnosis of PTC in thyroid nodules.
  
  
  BACKGROUND
  FNAB is the most reliable diagnostic test to discriminate between malignant and benign thyroid nodules, but nondiagnostic results remain a clinical management dilemma. BRAF(T1799A) mutation is the most prevalent genetic alteration in thyroid cancers and is specific for PTC, characteristics that make it the most potentially helpful genetic tool to improve the diagnostic accuracy of FNAB.
  
  
  METHODS
  An exhaustive recruitment of all patients subjected to thyroid FNAB in our institution during 4 years was performed. BRAF(T1799A) mutation was determined on thyroid FNAB specimens by PCR and restriction fragment length polymorphism, plus direct sequencing in positive samples.
  
  
  RESULTS
  BRAF(T1799A) mutation on FNAB detected 47.2% (17/36) of PTC cases. It confirmed preoperatively 45.5% (5/11) of the PTC cases in the indeterminate category and decreased the rate of cytopathology false-negatives in 33.3% (6/18), improving the combined (BRAF(T1799A) mutation + cytopathological analysis) sensitivity of the detection of PTC on FNAB in 16.7%.
  
  
  CONCLUSIONS
  BRAF(T1799A) mutation improves the diagnosis of PTC on FNAB, mainly because of the detection of cytopathology false-negatives, and it can be helpful in the routine analysis of thyroid nodules, especially in clinical settings with moderate sensitivity to detect PTC on FNAB.
authors.affiliation: Department of Nuclear Medicine, Virgen de las Nieves University Hospital, Granada, Spain. marisacgarre@gmail.com
authors.forename: Marisa
authors.initials: M
authors.lastname: Cañadas-Garre
authors.forename: Patricia
authors.initials: P
authors.lastname: Becerra-Massare
authors.forename: Martín
authors.initials: M
authors.lastname: López de la Torre-Casares
authors.forename: Jesús
authors.initials: J
authors.lastname: Villar-del Moral
authors.forename: Susana
authors.initials: S
authors.lastname: Céspedes-Mas
authors.forename: Ricardo
authors.initials: R
authors.lastname: Vílchez-Joya
authors.forename: Teresa
authors.initials: T
authors.lastname: Muros-de Fuentes
authors.forename: Carlos
authors.initials: C
authors.lastname: García-Calvente
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Piédrola-Maroto
authors.forename: Miguel A
authors.initials: MA
authors.lastname: López-Nevot
authors.forename: Rosa
authors.initials: R
authors.lastname: Montes-Ramírez
authors.forename: José M
authors.initials: JM
authors.lastname: Llamas-Elvira
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D002291:Carcinoma, Papillary / Q000235:genetics* / Q000473:pathology*; D004273:DNA, Neoplasm / Q000032:analysis / Q000302:isolation & purification; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011446:Prospective Studies; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000473:pathology*; D055815:Young Adult
chemical_list: D004273:DNA, Neoplasm; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf