title: Sonographic characteristics suggesting papillary thyroid carcinoma according to nodule size.
abstract: OBJECTIVE
  To determine differences in ultrasonography (US) features suggesting papillary thyroid carcinoma (PTC) between nodules larger than 10 mm (large lesions) and nodules ≤10 mm in diameter (small lesions).
  
  
  METHODS
  We included 1,238 nodules in 1,173 patients that were confirmed through cytology or histopathology between February 2007 and June 2007 in the study. Nodules were divided into large lesions (571 lesions) and small lesions (667 lesions). Sonographic features were defined as composition, echogenicity, margin, calcifications, shape, and vascularity. Logistic regression analyses were performed to determine the odds ratios (OR) of each feature to predict PTC.
  
  
  RESULTS
  On multivariate analysis, irregular margin (OR = 37.788, P < 0.001), microcalcifications (OR = 17.799, P < 0.001), microlobulated margin (OR = 10.385, P < 0.001), and no vascularity (OR = 5.975, P < 0.001) were independent factors for PTC in the large lesions and irregular margin (OR = 7.185, P < 0.001), microlobulated margin (OR = 5.952, P < 0.001), microcalcifications (OR = 3.722, P < 0.001), marked hypoechogenicity (OR = 2.873, P = 0.004), and taller than wide shape (OR = 2.698, P < 0.001) were independent factors for PTC in the small lesions.
  
  
  CONCLUSIONS
  The OR of each US finding for predicting PTC is different between large and small lesions. Therefore, it would be helpful to weight certain US features according to nodule size when reporting thyroid nodules with different risks of PTC.
authors.affiliation: Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Ga Ram
authors.initials: GR
authors.lastname: Kim
authors.forename: Myung Hyun
authors.initials: MH
authors.lastname: Kim
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Moon
authors.forename: Woong Youn
authors.initials: WY
authors.lastname: Chung
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kwak
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002114:Calcinosis; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging* / Q000473:pathology; D002648:Child; D003581:Cytodiagnosis; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography; D055815:Young Adult