title: Ultrasound-guided fine-needle aspiration biopsy of the thyroid: methods to decrease the rate of unsatisfactory biopsies in the absence of an on-site pathologist.
abstract: OBJECTIVE
  The rate of unsatisfactory samples from ultrasound-guided fine-needle aspirations of thyroid nodules varies widely in the literature. We aimed to evaluate our thyroid ultrasound-guided fine-needle aspiration biopsy technique in the absence of on-site microscopic examination by a pathologist; determine factors that affect the adequacy rate, such as the number of needle passes and needle size; compare our results with the literature; and establish an optimal technique.
  
  
  METHODS
  We performed a retrospective review of cytopathology reports from 252 consecutive thyroid ultrasound-guided fine-needle aspiration biopsies performed by a radiologist between 2005 and 2010 in our hospital's radiology department. Sample adequacy, the number of needle passes, and needle size were determined. There was an on-site cytologist who prepared slides immediately after fine-needle aspiration but no on-site microscopic assessment of sample adequacy to guide the number of needle passes that should be performed. Cytopathology biopsy reports were classified as either unsatisfactory or satisfactory samples for diagnosis; the latter consisted of benign, malignant, and undetermined diagnoses.
  
  
  RESULTS
  Seventy-seven biopsies were performed with 1 needle pass, 124 with 2 needle passes, and 51 with 3 needle passes. The rates of unsatisfactory biopsies were 33.8%, 23.4% (odds ratio [OR] 0.599 [95% confidence interval {CI}, 0.319-1.123]; P = .110), and 13.7% (OR 0.312 [95% CI, 0.124-0.788]; P = .014), respectively.
  
  
  CONCLUSIONS
  In a hospital in which there is no on-site pathologist, a 3-pass method increases the specimen satisfactory rate by 20% compared with 1 pass, achieves similar rates to the literature, and provides a basis for further improvement of our practice.
authors.affiliation: University of Montreal Hospital Center, University of Montreal Faculty of Medicine, Montreal, Quebec, Canada. cyrillenaim@yahoo.ca
authors.forename: Cyrille
authors.initials: C
authors.lastname: Naïm
authors.forename: Ramy
authors.initials: R
authors.lastname: Karam
authors.forename: Donald
authors.initials: D
authors.lastname: Eddé
mesh_terms: D044963:Biopsy, Fine-Needle / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D003937:Diagnosis, Differential; D006801:Humans; D016017:Odds Ratio; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013961:Thyroid Gland / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000648:ultrastructure; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000648:ultrastructure; D018084:Ultrasonography, Interventional / Q000379:methods*