title: Predictors of non-diagnostic cytology in surgeon-performed ultrasound guided fine needle aspiration of thyroid nodules.
abstract: BACKGROUND
  Fine needle aspiration (FNA) is the standard of care for the diagnostic work-up of thyroid nodules but despite its proven utility, the non-diagnostic rate for thyroid FNA ranges from 6-36%. A non-diagnostic FNA is problematic for the clinician and patient because it can result in repeated procedures, multiple physician visits, and a delay in definitive treatment. Surgeon-performed FNA has been shown to be safe, cost-effective, as accurate as those performed by other clinicians, and has the added benefit of decreasing wait times to surgery. Several studies have examined rates and factors that may be predictive of a non-diagnostic cytology in non-surgeon FNA, but none have evaluated this in surgeon-performed thyroid FNA. If these factors are unique in surgeon-performed vs. non-surgeon performed thyroid FNA, then patients may be more appropriately triaged to FNA by alternate clinicians.
  
  
  OBJECTIVE
  The purpose of this study was to determine the rate and factors predictive of a non-diagnostic FNA in surgeon performed ultrasound-guided FNA of thyroid nodules.
  
  
  METHODS
  We conducted a retrospective review of all adult patients who underwent thyroid FNA by a staff, fellow, or resident Otolaryngologist at the University of Alberta between January 2011 and June 2013. Factors analyzed included patient factors, thyroid characteristics, nodule characteristics, and surgeon level of training and experience. Univariate and multivariate binary logistic regression analysis were performed.
  
  
  RESULTS
  131 patients (180 nodules) were reviewed. The non-diagnostic rate was 23%. Nodules with predominant cystic component, those less than 1 cm, and resident-performed FNA were associated with non-diagnostic cytology (p = 0.001, p = 0.02, p = 0.04 respectively). A cystic nodule was the only independent predictor of non-diagnostic FNA on multivariate analysis (OR = 4.441, 95% CI [1.785-11.045], p = 0.001).
  
  
  CONCLUSIONS
  The rate of non-diagnostic thyroid FNA performed by a surgeon with ultrasound guidance is similar to other clinicians. A cystic nodule is a strong independent predictor of non-diagnostic cytology. Non-cystic nodules may particularly benefit from surgeon-performed thyroid FNA due to the high diagnostic rate and potential for earlier definitive management.
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Andre
authors.initials: A
authors.lastname: Isaac
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Caroline C
authors.initials: CC
authors.lastname: Jeffery
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Hadi
authors.initials: H
authors.lastname: Seikaly
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Hani
authors.initials: H
authors.lastname: Al-Marzouki
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Harris
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, University of Alberta, #603-10649 Saskatchewan Drive, Edmonton, AB T6E 6S8 Canada.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: O'Connell
mesh_terms: D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D002170:Canada; D005260:Female; D006801:Humans; D061705:Image-Guided Biopsy; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016606:Thyroid Nodule / Q000175:diagnosis*; D018084:Ultrasonography, Interventional
keywords: Diagnostic yield; FNA; Thyroid nodule; Ultrasound