title: The role of ultrasound findings in the management of thyroid nodules with atypia or follicular lesions of undetermined significance.
abstract: BACKGROUND
  Atypia or follicular lesions of undetermined significance (AUS/FLUS) is a broad cytological category in the Bethesda system for classifying thyroid cytology. This study investigated the diagnostic accuracy of ultrasound (US) analysis of thyroid nodules with AUS/FLUS.
  
  
  METHODS
  Of 5062 subjects with nodules subjected to fine-needle aspiration cytology (FNACs) at our institution from January 2010 through May 2012, 383 met the Bethesda criteria for AUS/FLUS. After excluding subjects who had a history of thyroid cancer, who only underwent repeat FNA or who underwent no further examinations, we selected 249 subjects who had subsequently undergone a core-needle biopsy and/or surgery. Of these, 100 were found to have malignant nodules (40·2%), 122 had benign nodules (49%), and 27 had nodules with indeterminate status (10·8%). We compared specific US parameters, including size, location, content, shape, margin, echogenicity, echotexture and calcification across these subject groups.
  
  
  RESULTS
  Multivariate analysis revealed that malignancy was associated with taller-than-wide shape (TDW) (OR = 8·43, P = 0·002), ill-defined margin (OR = 3·23, P = 0·002) and marked hypoechogenicity. (OR = 3·61, P = 0·001). The specificity and positive predictive values of TDW were 98% and 90·6%,respectively. The specificity and positive predictive values of 'TDW and marked hypoechogenicity' were both 100%.
  
  
  CONCLUSIONS
  US findings play a complementary role in the diagnosis of thyroid nodules with AUS/FLUS. In case of highly suspicious US findings such as 'TDW and marked hypoechogenicity', could be very helpful in the diagnosis of malignancy.
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Dankook University Hospital, Seoul, Korea.
authors.forename: Won Sang
authors.initials: WS
authors.lastname: Yoo
authors.forename: Hoon Sung
authors.initials: HS
authors.lastname: Choi
authors.forename: Sun Wook
authors.initials: SW
authors.lastname: Cho
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Moon
authors.forename: Kyung Won
authors.initials: KW
authors.lastname: Kim
authors.forename: Hyo Jin
authors.initials: HJ
authors.lastname: Park
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Park
authors.forename: Sang Il
authors.initials: SI
authors.lastname: Choi
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Choi
authors.forename: Soo
authors.initials: S
authors.lastname: Lim
authors.forename: Ka Hee
authors.initials: KH
authors.lastname: Yi
authors.forename: Do Joon
authors.initials: DJ
authors.lastname: Park
authors.forename: Hak Chul
authors.initials: HC
authors.lastname: Jang
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Park
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000175:diagnosis / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000175:diagnosis / Q000000981:diagnostic imaging*; D014463:Ultrasonography