title: Pediatric thyroid nodules: ultrasonographic characteristics and inter-observer variability in prediction of malignancy.
abstract: BACKGROUND
  Pediatric thyroid nodules, while uncommon, have high malignancy risk. The objectives of the study were (1) to identify sonographic features predictive of malignancy; (2) to create a prediction model; and (3) to assess inter-observer agreement among radiologists.
  
  
  METHODS
  All available cases of thyroid nodules, surgically removed between 2000 and 2009. Three radiologists reviewed the sonographic images; 2 pathologists reviewed the tissue specimens. Adult prediction models were applied. Interobserver variability was assessed.
  
  
  RESULTS
  Twenty-seven subjects, mean age 13.1±3.4 years, were included. Nineteen nodules were differentiated thyroid carcinomas. On multivariate analysis, size was the only significant predictor of malignancy. On recursive partitioning analysis, size >35 mm with microcalcification and ill-defined margins yielded the best prediction model. Radiologist inter-observer agreement regarding malignancy was moderate (κ=0.50).
  
  
  CONCLUSIONS
  Larger size, microcalcifications and ill-defined margins on ultrasound demonstrate the best predictive model for malignancy in the pediatric population. Experienced pediatric radiologists demonstrate moderate inter-observer agreement in prediction of malignancy.
authors.forename: Dror
authors.initials: D
authors.lastname: Koltin
authors.forename: Clodagh S
authors.initials: CS
authors.lastname: O'Gorman
authors.forename: Amanda
authors.initials: A
authors.lastname: Murphy
authors.forename: Bo
authors.initials: B
authors.lastname: Ngan
authors.forename: Alan
authors.initials: A
authors.lastname: Daneman
authors.forename: Oscar M
authors.initials: OM
authors.lastname: Navarro
authors.forename: Cristián
authors.initials: C
authors.lastname: García
authors.forename: Eshetu G
authors.initials: EG
authors.lastname: Atenafu
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Wasserman
authors.forename: Jill
authors.initials: J
authors.lastname: Hamilton
authors.forename: Marianna
authors.initials: M
authors.lastname: Rachmiel
mesh_terms: D000293:Adolescent; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003649:Decalcification, Pathologic / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006776:Hospitals, Pediatric; D006801:Humans; D008297:Male; D015588:Observer Variation; D009864:Ontario / Q000453:epidemiology; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012306:Risk; D013961:Thyroid Gland / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D047368:Tumor Burden; D014463:Ultrasonography