title: Single-session treatment of benign cystic thyroid nodules with ethanol versus radiofrequency ablation: a prospective randomized study.
abstract: OBJECTIVE
  To compare volume reduction of single-session ethanol ablation (EA) and radiofrequency (RF) ablation for cystic thyroid nodule treatment.
  
  
  METHODS
  All patients gave written informed consent to participate in this prospective institutional review board-approved study. From May 6, 2010, to August 8, 2011, in this single-institutional, noninferiority trial, 50 patients, each with a single cystic thyroid nodule, were randomly assigned to EA (25 patients; mean age for women, 45.7 years, and for men, 37.5 years) or RF ablation (25 patients; mean age for women, 45.1 years, and for men, 43.7 years) treatment. Internal fluid was aspirated prior to EA or RF ablation. Primary end point was the volume reduction ratio (percentage) at 6-month follow-up; the noninferiority margin was chosen as -8% (EA minus RF ablation). Secondary end points included therapeutic success rate, improvement of symptoms and cosmetic problems, and number of major complications. Analysis was performed primarily in intention-to-treat manner. A one-sided 95% confidence interval (CI) for the mean difference in volume reduction ratio 6 months after treatment was calculated to test for noninferiority. Subsequent superiority comparison of EA with RF ablation on a condition of establishment of the noninferiority of EA to RF ablation was preplanned and used two-sided 95% CI of the outcome difference.
  
  
  RESULTS
  The mean volume reduction was 96.9% in EA and 93.3% in RF ablation (n = 21 for each) (difference, 3.6%; lower bound of the one-sided 95% CI of the difference, 1.2%), thus demonstrating the noninferiority of EA to RF ablation. Two-sided 95% CI of the outcome difference was 0.7% to 6.5%, demonstrating significant superiority of EA to RF ablation. All patients demonstrated therapeutic success (P > .99). Mean symptom and cosmetic scores showed no significant difference in either group (P = .806 and P = .682, respectively). There were no major complications (P > .99).
  
  
  CONCLUSIONS
  EA may be the first-line treatment modality for cystic thyroid nodules, which has comparable therapeutic efficacy to, but is less expensive than, RF ablation.
authors.affiliation: Departments of Radiology, Internal Medicine, and Pathology, Thyroid Center, Daerim St Mary's Hospital, Seoul, Korea; Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 86 Asanbyeongwon-Gil, Songpa-gu, Seoul 138-736, Korea.
authors.forename: Jin Yong
authors.initials: JY
authors.lastname: Sung
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Baek
authors.forename: Kyu Sun
authors.initials: KS
authors.lastname: Kim
authors.forename: Ducky
authors.initials: D
authors.lastname: Lee
authors.forename: Hyunju
authors.initials: H
authors.lastname: Yoo
authors.forename: Jae Kyun
authors.initials: JK
authors.lastname: Kim
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D003560:Cysts / Q000000981:diagnostic imaging* / Q000628:therapy*; D000431:Ethanol / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012597:Sclerosing Solutions / Q000008:administration & dosage; D016606:Thyroid Nodule / Q000000981:diagnostic imaging* / Q000628:therapy*; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000379:methods*
chemical_list: D012597:Sclerosing Solutions; D000431:Ethanol