title: Diagnostic value of ultrasonography to distinguish between benign and malignant lesions in the management of thyroid nodules.
abstract: OBJECTIVE
  We analyzed the sonographic characteristics of thyroid nodules and assessed the diagnostic value of ultrasonography in order to distinguish between benign and malignant lesions in terms of the management of thyroid nodules.
  
  
  METHODS
  We retrospectively analyzed the sonographic features of thyroid nodules in 580 patients who had been examined with fine-needle aspiration cytology or who underwent surgery for a thyroid nodule. The sonographic features that suggested malignancy include microcalcifications, an irregular or microlobulated margin, marked hypoechogenicity, and a shape that was taller than it was wide. The presence of one or more of these features indicated classification as category 3 (malignant). The absence of all of these features indicated classification as category 2 (benign). Presence of an anechogenic cystic nodule was classified as category 1 (benign).
  
  
  RESULTS
  Of 124 lesions classified as category 3, 60 of the lesions were malignant. Of 418 lesions classified as category 1 or 2, 409 were benign. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy based on the sonographic classification method were 87.0%, 86.5%, 48.4%, 97.8%, and 86.5%, respectively.
  
  
  CONCLUSIONS
  Our results identified this sonographic classification as a useful tool in the differentiation of malignant nodules from benign nodules. In view of the high negative predictive value of sonographic classification, a more aggressive approach is recommended only for category 3 nodules.
authors.affiliation: Department of Internal Medicine, The Catholic University of Korea, College of Medicine, Seoul, Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Tae
authors.forename: Dong Jun
authors.initials: DJ
authors.lastname: Lim
authors.forename: Ki Hyun
authors.initials: KH
authors.lastname: Baek
authors.forename: Woo Chan
authors.initials: WC
authors.lastname: Park
authors.forename: Youn Soo
authors.initials: YS
authors.lastname: Lee
authors.forename: Jung Eun
authors.initials: JE
authors.lastname: Choi
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Moo Il
authors.initials: MI
authors.lastname: Kang
authors.forename: Bong Yun
authors.initials: BY
authors.lastname: Cha
authors.forename: Ho Young
authors.initials: HY
authors.lastname: Son
authors.forename: Kwang Woo
authors.initials: KW
authors.lastname: Lee
authors.forename: Sung Koo
authors.initials: SK
authors.lastname: Kang
mesh_terms: D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging*; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000628:therapy; D014463:Ultrasonography