title: Risk stratification of thyroid nodules with Bethesda category III results on fine-needle aspiration cytology: The additional value of acoustic radiation force impulse elastography.
abstract: To assess the value of conventional ultrasound, conventional strain elastography (CSE) and acoustic radiation force impulse (ARFI) elastography in differentiating likelihood of malignancy for Bethesda category III thyroid nodules. 103 thyroid nodules with Bethesda category III results on fine-needle aspiration cytology (FNAC) in 103 patients were included and all were pathologically confirmed after surgery. Conventional ultrasound, CSE and ARFI elastography including ARFI imaging and point shear wave speed (SWS) measurement were performed. Univariate and multivariate analyses were performed to identify the independent factors associated with malignancy. Area under the receiver operating characteristic curve (Az) was calculated to assess the diagnostic performance. Pathologically, 65 nodules were benign and 38 were malignant. Significant differences were found between benign and malignant nodules in ARFI. The cut-off points were ARFI imaging grade ≥ 4, SWS > 2.94 m/s and SWS ratio > 1.09, respectively. ARFI imaging (Az: 0.861) had the highest diagnostic performance to differentiate malignant from benign nodules, following by conventional ultrasound (Az: 0.606 - 0.744), CSE (Az: 0.660) and point SWS measurement (Az: 0.725 - 0.735). Multivariate logistic regression analysis showed that ARFI imaging grade ≥ 4 was the most significant independent predictor. The combination of ARFI imaging with point SWS measurement significantly improved the specificity (100% vs. 80.0%) and positive predictive value (100 % vs. 72.9%) in comparison with ARFI imaging alone. ARFI elastography is a useful tool in differentiating malignant from benign thyroid nodules with Bethesda category III results on FNAC.
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Chong-Ke
authors.initials: CK
authors.lastname: Zhao
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Hui-Xiong
authors.initials: HX
authors.lastname: Xu
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Jun-Mei
authors.initials: JM
authors.lastname: Xu
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Cheng-Yu
authors.initials: CY
authors.lastname: Sun
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Bo-Ji
authors.initials: BJ
authors.lastname: Liu
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Xiao-Wan
authors.initials: XW
authors.lastname: Bo
authors.affiliation: Department of Medical Ultrasound, Shanghai Tenth People's Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai 200072, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai 200072, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Endocrinology & Metabolism, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.
authors.forename: Shen
authors.initials: S
authors.lastname: Qu
mesh_terms: D000236:Adenoma / Q000175:diagnosis; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D003581:Cytodiagnosis / Q000379:methods; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006042:Goiter / Q000175:diagnosis; D050031:Hashimoto Disease / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D016606:Thyroid Nodule / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000601:surgery; D014463:Ultrasonography / Q000379:methods*
keywords: Bethesda category III; acoustic radiation force impulse elastography; fine-needle aspiration cytology; thyroid nodules; ultrasound