title: Thyroid Ultrasound-Guided Fine-Needle Aspiration: The Positive Influence of On-Site Adequacy Assessment and Number of Needle Passes on Diagnostic Cytology Rate.
abstract: OBJECTIVE
  Nondiagnostic cytology is the most important limitation of thyroid ultrasound-guided fine-needle aspiration (US-FNA). This study aimed to identify factors associated with the adequacy rate of thyroid US-FNA.
  
  
  METHODS
  Consecutive thyroid US-FNAs (2006-2013) were retrospectively included. Attending radiologists, radiology fellows and radiology residents performed US-FNA, usually involving 2-3 needle passes. In more recent years, rapid on-site adequacy assessment (ROSAA) was performed to ensure specimen adequacy. US characteristics, procedural variations and cytology results were extracted from US and pathology reports and statistically evaluated.
  
  
  RESULTS
  Diagnostic cytology was obtained in 64.6% of 1,381 thyroid US-FNAs. Factors associated with nondiagnostic cytology were ROSAA (74.6% diagnostic cytology, OR 0.55, 95% CI 0.42-0.71), ≥3 clinic visits for US-FNA of the same thyroid nodule (54.7%, OR 1.56, 95% CI 1.16-2.10) and increased intranodular vascularization (51.8%, OR 1.73, 95% CI 1.17-2.57). With ROSAA, an increasing number of needle passes demonstrated improving adequacy rates. The adequacy rate was not operator-dependent.
  
  
  CONCLUSIONS
  This study demonstrates that ROSAA improves the adequacy rate of thyroid US-FNA. Without ROSAA, we recommend performing at least 3 needle passes. Less diagnostic cytology is obtained from nodules with increased intranodular vascularization or from those undergoing US-FNA ≥3 times.
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: de Koster
authors.forename: Jakob W
authors.initials: JW
authors.lastname: Kist
authors.forename: Menno R
authors.initials: MR
authors.lastname: Vriens
authors.forename: Inne H M
authors.initials: IH
authors.lastname: Borel Rinkes
authors.forename: Gerlof D
authors.initials: GD
authors.lastname: Valk
authors.forename: Bart
authors.initials: B
authors.lastname: de Keizer
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013959:Thyroid Diseases / Q000175:diagnosis*; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis*