title: Ultrasound elastography is not superior to grayscale ultrasound in predicting malignancy in thyroid nodules.
abstract: BACKGROUND
  Several studies have evaluated the ability of ultrasound elastography (USE) to diagnose malignant nodules. However, these studies had important limiting factors, selection bias and small sample size. The aims of the present study were to prospectively assess, in a large group of patients, the diagnostic power of USE for detecting malignancy in thyroid nodules, and to compare this technique with B-mode grayscale ultrasonography (BUS) and power Doppler ultrasonography (PD).
  
  
  METHODS
  There were 194 patients with 237 thyroid nodules who were examined using BUS, PD, and USE. USE scores were classified according to the elasticity: score 1 as high, score 2 as intermediate, and score 3 as low (i.e., a high degree of stiffness). Fine-needle aspiration cytology (FNAC) was performed in all nodules at least two different times. Nodules having two benign FNAC readings that did not change the diameter during a 6-month follow-up period were classified as benign. Patients having thyroid nodules with indeterminate, suspicious, or malignant cytology had total or hemithyroidectomy to remove the nodule and treat the malignancy.
  
  
  RESULTS
  Fifty eight (25%) nodules in 45 (23%) patients were found to be malignant. USE had a limited sensitivity and a positive predictive value in detecting malignant thyroid nodules and was not superior to BUS. USE had almost the same specificity and a negative predictive value as BUS. A power Doppler type-3 pattern was not of sufficient sensitivity to detect malignancies in thyroid nodules.
  
  
  CONCLUSIONS
  In contrast to earlier reports, this current study noted a lower sensitivity and specificity of USE for the diagnosis of malignancy in thyroid nodules than previously reported.
authors.affiliation: Department of Endocrinology and Metabolism, Ankara University School of Medicine, Ankara, Turkey. ugurunluturk@gmail.com
authors.forename: Uğur
authors.initials: U
authors.lastname: Unlütürk
authors.forename: Murat Faik
authors.initials: MF
authors.lastname: Erdoğan
authors.forename: Ozgür
authors.initials: O
authors.lastname: Demir
authors.forename: Sevim
authors.initials: S
authors.lastname: Güllü
authors.forename: Nilgün
authors.initials: N
authors.lastname: Başkal
mesh_terms: D000328:Adult; D000368:Aged; D054459:Elasticity Imaging Techniques; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013961:Thyroid Gland / Q000000981:diagnostic imaging* / Q000473:pathology; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D016606:Thyroid Nodule / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology