title: Fine-needle aspiration of follicular patterned lesions of the thyroid: diagnosis, management, and follow-up according to thyroid Bethesda system.
abstract: OBJECTIVE
  The goal of this study was to report an experience with thyroid fine-needle aspiration (FNA) cases that can be placed into National Cancer Institute-designated thyroid FNA diagnostic categories for follicular patterned lesions divided into three diagnostic categories: follicular lesion of undetermined significance/atypia of undetermined significance (AUS/FLUS), suspicious for follicular neoplasm (SFON), and suspicious for malignancy.
  
  
  METHODS
  The study cohort included 4,284 cases for the period between January 2007 and July 2011 and all available follow-up data was obtained. All cases classified as 'atypical' and 'rule out follicular neoplasm' were included in the AUS/FLUS category (n = 3,903), whereas cases classified as 'suspicious for' or 'consistent with follicular or Hürthle cell neoplasm' (n = 381) were included in the SFON diagnostic category and compared with histopathologic follow-up.
  
  
  RESULTS
  During this period, 14,628 thyroid FNAs were reported in 12,238 patients. Repeat FNA (RFNA) was performed in 1,366/3,903 (35%) patients classified as AUS/FLUS. Histologic outcome data was available in 1,756/3,903 (45%) cases diagnosed as AUS/FLUS and 243/381 (64%) cases diagnosed as SFON. The rate of malignancy in AUS/FLUS cases with and without RFNA was 29 and 14% respectively, and it was 26% in SFON cases.
  
  
  CONCLUSIONS
  The current data shows that the malignancy rates differ between categories and AUS/FLUS cases are best managed by RFNA for selection of cases that can benefit from surgical excision.
authors: Pathology Department, Ankara Training and Research Hospital, Ankara, Turkey. olgupatoloji@yahoo.com
authors: Hüseyin
authors: H
authors: Ustün
authors: Hesna Müzeyyen
authors: HM
authors: Astarcı
authors: Canan
authors: C
authors: Altunkaya
authors: Sırma
authors: S
authors: Yılmaz
authors: Ahmet
authors: A
authors: Barın
authors: Serap
authors: S
authors: Ekici
authors: Muzaffer
authors: M
authors: Caydere
mesh_terms: D044963:Biopsy, Fine-Needle; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016606:Thyroid Nodule / Q000175:diagnosis* / Q000601:surgery*