title: Radiofrequency ablation vs. microwave ablation for patients with benign thyroid nodules: a propensity score matching study.
abstract: OBJECTIVE
  To compare the efficacy and the safety of radiofrequency ablation and microwave ablation for treatment of benign thyroid nodules using a propensity score matching study design.
  
  
  METHODS
  Two hundred and sixty patients with benign thyroid nodules were studied retrospectively, including 102 patients treated with radiofrequency ablation and 158 treated with microwave ablation. To reduce confounding bias due to retrospective assignment, propensity score matching was performed to balance the preablation data of the two groups. After matching, a total of 102 patient pairs (1:1) were created. The volume reduction ratio, therapeutic success rate, symptom and cosmetic score, and major complication were compared between the two groups at 1, 3, 6, and 12 months after treatment.
  
  
  RESULTS
  Between the well-matched groups, no significant differences were found in all nodule volume-related end points at 6 months (volume reduction ratio: 79.4 vs. 77.2 %, P = 0.108; symptom score: 2.1 vs. 1.9, P = 0.456; cosmetic score: 2.1 vs. 2.3, P = 0.119; therapeutic success rate: 99 vs. 97 %, P = 0.621) and 12 months (volume reduction ratio: 83.6 vs. 81.6 %, P = 0.144; symptom score: 1.5 vs. 1.5, P = 0.869; cosmetic score: 1.6 vs. 1.7, P = 0.409; therapeutic success rate: 100 vs. 100 %, P > 0.99) after treatment. No major complications occurred in either group (P > 0.99).
  
  
  CONCLUSIONS
  With well-matched groups and consistent procedure design, our results demonstrated that the volume reduction ratio, therapeutic success rate, symptom and cosmetic score, and complications related to treatment for the two techniques are equivalent. Radiofrequency ablation and microwave ablation are both effective and safe methods in treating benign thyroid nodules.
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai, 200072, China.|Department of Medical Ultrasound, Yantai Affiliated Hospital, Binzhou Medical University, Yantai, Shandong, 264100, China.|Thyroid Institute, Tongji University School of Medicine, Shanghai, 200072, China.|Shanghai Center for Thyroid Diseases, Shanghai, 200072, China.
authors.forename: Wen-Wen
authors.initials: WW
authors.lastname: Yue
authors.affiliation: Department of Medical Ultrasound, Yantai Affiliated Hospital, Binzhou Medical University, Yantai, Shandong, 264100, China. wsr7762808@hotmail.com.
authors.forename: Shu-Rong
authors.initials: SR
authors.lastname: Wang
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, 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: Feng
authors.initials: F
authors.lastname: Lu
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, 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: Li-Ping
authors.initials: LP
authors.lastname: Sun
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, 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: Le-Hang
authors.initials: LH
authors.lastname: Guo
authors.affiliation: Department of Medical Ultrasound, Yantai Affiliated Hospital, Binzhou Medical University, Yantai, Shandong, 264100, China.
authors.forename: Yong-Lin
authors.initials: YL
authors.lastname: Zhang
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, 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-Long
authors.initials: XL
authors.lastname: Li
authors.affiliation: Department of Medical Ultrasound, Tenth People's Hospital of Tongji University, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai, 200072, China. xuhuixiong@126.com.|Thyroid Institute, Tongji University School of Medicine, Shanghai, 200072, China. xuhuixiong@126.com.|Shanghai Center for Thyroid Diseases, Shanghai, 200072, China. xuhuixiong@126.com.
authors.forename: Hui-Xiong
authors.initials: HX
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008872:Microwaves; D008875:Middle Aged; D057216:Propensity Score; D012189:Retrospective Studies; D016606:Thyroid Nodule / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome; D014463:Ultrasonography
keywords: Benign thyroid nodule; Microwave ablation; Radiofrequency ablation; Thermal ablation; Ultrasound