title: Fine needle aspiration cytology of the thyroid: a cytohistologic study with evaluation of discordant cases.
abstract: OBJECTIVE
  To analyze the diagnostic efficacy of fine needle aspiration cytology (FNAC) in the initial evaluation of thyroid nodules, with special emphasis on discrepant cytologic diagnoses.
  
  
  METHODS
  A total of 192 thyroid fine needle aspirates with subsequent histopathologic follow-up were analyzed. The cytologic diagnoses were divided into 4 categories: positive for malignancy, negative for malignancy, indeterminate for diagnosis and nondiagnostic. The detailed cytologic features were studied along with histopathology sections in all these cases by 2 observers (S.J. and P.D) independently.
  
  
  RESULTS
  Cytohistologic correlation was seen in 78.1% of cases and discordance in 21.9%. Indeterminate diagnoses accounted for 15.1% of cases. The majority of these were "follicular neoplasms." The overall sensitivity was 84.44% and specificity 99.11 %. A false positive diagnosis was made in 1 case (0.5%), proven a follicular adenoma on histopathologic examination. A false negative diagnosis was seen in 3.6% of cases. These were cases of papillary microcarcinoma.
  
  
  CONCLUSIONS
  FNAC is a safe, sensitive and specific technique in the initial evaluation of thyroid nodules. A correct cytologic diagnosis can be achieved in a majority of cases, thus obviating the need for a second surgical intervention. A careful and diligent search for various cytologic features and accurate sampling can help in reducing the number of indeterminate, false positive and false negative diagnoses.
authors.affiliation: Department of Cytology, Kuwait Cancer Control Center, Sufat. sanjayjogai@rediffmail.com
authors.forename: Sanjay
authors.initials: S
authors.lastname: Jogai
authors.forename: Aisha
authors.initials: A
authors.lastname: Al-Jassar
authors.forename: Labiba
authors.initials: L
authors.lastname: Temmim
authors.forename: Pranab
authors.initials: P
authors.lastname: Dey
authors.forename: Aaron O
authors.initials: AO
authors.lastname: Adesina
authors.forename: H G
authors.initials: HG
authors.lastname: Amanguno
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000473:pathology; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle / Q000592:standards; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D004847:Epithelial Cells / Q000473:pathology*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000473:pathology*; D016606:Thyroid Nodule / Q000473:pathology*