title: Shear-Wave Elastography for Papillary Thyroid Carcinoma can Improve Prediction of Cervical Lymph Node Metastasis.
abstract: This study aimed to investigate whether the elasticity index of shear-wave elastography (SWE) can predict cervical lymph node (LN) metastasis of papillary thyroid carcinoma (PTC).
  
  
  
  This retrospective study included 363 patients with a surgical diagnosis of PTC who underwent preoperative SWE evaluation. The elasticity indices of PTC (Emean, Emax, Emin, Eratio-p, and Eratio-m) and gray-scale ultrasound (US) parameters (extrathyroidal extension, multifocality, and cervical LN metastasis) were correlated with the pathologic staging parameters. The optimal cutoff values for the elasticity indices were determined for the prediction of cervical LN metastasis, and diagnostic performance was compared between gray-scale US and the combined application of gray-scale US and SWE.
  
  
  
  The findings showed Emeanand Emaxto be associated with central LN metastasis (P = 0.037) and Eminto be associated with lateral LN metastasis (P = 0.015). An Emeanvalue higher than 124 kPa or an Emaxvalue higher than 138 kPa with suspicious gray-scale US findings improved the sensitivity and area under the curve (AUC) for predicting central LN metastasis (sensitivity, 45.4 and 44.6 % vs. 28 %, P < 0.001; AUC, 0.659 and 0.667 vs. 0.615, P = 0.011 and 0.019), whereas an Eminvalue higher than 63 kPa with suspicious gray-scale US findings improved the sensitivity and AUC for predicting lateral LN metastasis (sensitivity, 95.8 vs. 75 %, P = 0.025; AUC, 0.924 vs. 0.871, P = 0.047).
  
  
  
  The quantitative elasticity index of PTC on preoperative SWE could be useful for predicting cervical LN metastasis.
authors.affiliation: Department of Radiology, CHA Bundang Medical Center, CHA University, Gyeonggi-do, Republic of Korea.
authors.forename: Ah Young
authors.initials: AY
authors.lastname: Park
authors.affiliation: Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea. chrismd@hanmail.net.
authors.forename: Jeong-Ah
authors.initials: JA
authors.lastname: Kim
authors.affiliation: Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Son
authors.affiliation: Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Youk
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002291:Carcinoma, Papillary / Q000000981:diagnostic imaging* / Q000556:secondary* / Q000601:surgery; D004548:Elasticity; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009333:Neck; D037981:Neck Dissection; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D057234:Preoperative Period; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D055815:Young Adult