title: Improved preoperative definitive diagnosis of papillary thyroid carcinoma in FNAs prepared with both ThinPrep and conventional smears compared with FNAs prepared with ThinPrep alone.
abstract: BACKGROUND
  ThinPrep (TP) liquid-based preparations are increasingly being used in nongynecologic specimens. Few studies have evaluated TP as a sole diagnostic modality in the setting of thyroid fine-needle aspiration (T-FNA). Herein, the authors evaluate the usefulness of TP as a sole diagnostic modality in a nonsplit sample.
  
  
  METHODS
  Consecutive T-FNAs were identified at 2 tertiary care institutions; 1 institution processed thyroid FNA entirely with TP, and the other used a combination of TP and conventional preparations (CP). Cytodiagnoses, surgical pathology, and/or clinical follow-up were recorded. Performance parameters for the 2 settings were compared.
  
  
  RESULTS
  A cytologic diagnosis of positive for malignancy was correct in 98.8% of TP + CP cases and in 100% of TP cases. Papillary thyroid carcinoma cases were definitively diagnosed in 53.1% of T-FNAs prepared by TP + CP compared with 34.4% of T-FNAs prepared with TP alone (P = .0015 by Fisher 2-tailed exact test). Of patients ultimately diagnosed with papillary thyroid carcinoma, 89% were initially treated by total thyroidectomy in the TP + CP group compared with 79.5% in the TP-only group (P = .027 by Fisher exact test).
  
  
  CONCLUSIONS
  TP as a sole preparatory technique does not improve the usefulness of T-FNA as a screening test. However, combining CP and TP increases the rate of definitive cytologic diagnosis of malignancy in papillary thyroid carcinoma. Thus, combining TP and CP enhances the diagnostic component of T-FNA.
authors.affiliation: Department of Pathology, Rhode Island Hospital, Providence, RI, USA.
authors.forename: Martin H
authors.initials: MH
authors.lastname: Luu
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Fischer
authors.forename: Latha
authors.initials: L
authors.lastname: Pisharodi
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Owens
mesh_terms: D044963:Biopsy, Fine-Needle; D002291:Carcinoma, Papillary / Q000175:diagnosis* / Q000601:surgery; D003581:Cytodiagnosis; D016591:Histocytological Preparation Techniques; D006801:Humans; D011300:Preoperative Care; D013048:Specimen Handling; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000601:surgery