title: Efficacy of microwave versus radiofrequency ablation for treatment of small hepatocellular carcinoma: experimental and clinical studies.
abstract: OBJECTIVE
  To prospectively compare microwave (MW) ablation using a modified internal cooled-shaft antenna with radiofrequency (RF) ablation in in vivo porcine liver and in patients with small hepatocellular carcinoma (sHCC).
  
  
  METHODS
  In an animal study, MW and RF ablations using a cooled-shaft antenna or internally cooled electrode were performed in in vivo porcine liver. Coagulation diameters of both ablations were compared. For clinical study, 42 patients with sHCC were treated with MW or RF ablation. Complete ablation (CA) and local tumour progression (LTP) were compared.
  
  
  RESULTS
  MW ablation produced significantly larger ablation zones than RF ablation in both porcine liver and sHCC with an ablated volume of 33.3 ± 15.6 cm(3) vs. 18.9 ± 9.1 cm(3) and 109.3 ± 58.3 cm(3) vs. 48.7 ± 30.5 cm(3), respectively. The CA rate was 95.5 % (21/22) for MW ablation and 95.0 % (19/20) for RF ablation. In a 5.1-month follow-up, the LTP rate was 18.2 % (4/22) in the MW ablation group and 15.0 % (3/20) in the RF ablation group.
  
  
  CONCLUSIONS
  MW ablation using a modified cooled-shaft antenna produces a larger ablation zone than RF ablation, with an efficacy similar to RF ablation in local tumour control. MW ablation is a safe and promising treatment of sHCC.
authors.affiliation: Department of Ultrasonic Intervention, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai 200438, China.
authors.forename: Guo-Jun
authors.initials: GJ
authors.lastname: Qian
authors.forename: Neng
authors.initials: N
authors.lastname: Wang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.forename: Yue Hong
authors.initials: YH
authors.lastname: Sheng
authors.forename: Jie-Qiong
authors.initials: JQ
authors.lastname: Zhao
authors.forename: Ming
authors.initials: M
authors.lastname: Kuang
authors.forename: Guang-Jian
authors.initials: GJ
authors.lastname: Liu
authors.forename: Meng-Chao
authors.initials: MC
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008872:Microwaves / Q000627:therapeutic use*; D008875:Middle Aged; D013552:Swine; D016896:Treatment Outcome; D014463:Ultrasonography