title: Percutaneous microwave ablation of hepatocellular carcinoma with a gas-cooled system: initial clinical results with 107 tumors.
abstract: OBJECTIVE
  To retrospectively review the results of hepatocellular carcinoma (HCC) treatment with a high-power, gas-cooled, multiantenna-capable microwave device.
  
  
  METHODS
  A total of 107 HCCs in 75 patients (65 men) with a mean age of 61 years (range, 44-82 y) were treated via percutaneous approach. Combination microwave ablation and transarterial chemoembolization was performed for 22 tumors in 19 patients with tumors larger than 4 cm (n = 10), tumors larger than 3 cm with ill-defined margins (n = 7), or lesions not identified with ultrasonography (n = 5). Mean tumor size was 2.1 cm (range, 0.5-4.2 cm), with median follow-up of 14 months, for ablation alone; compared with 3.7 cm (range, 1.0-7.0 cm) and 12 months, respectively, for combination therapy. All procedures were performed with a single microwave system (Certus 140) with one to three 17-gauge antennas.
  
  
  RESULTS
  Mean ablation time was 5.3 minutes (range, 1-11.5 min). All treatments were considered technically successful in a single session. Primary technique effectiveness rates were 91.6% (98 of 107) overall, 93.7% (89 of 95) for tumors 4 cm or smaller, and 75.0% (nine of 12) for tumors larger than 4 cm; and 91.8% (78 of 85) for ablation alone and 90.9% (20 of 22) for combination therapy. There was no major complication or procedure-related mortality. The overall survival rate was 76.0% at a median 14-month clinical follow-up, with most deaths related to end-stage liver disease (n = 11) or multifocal HCC (n = 5).
  
  
  CONCLUSIONS
  Treating HCC with a gas-cooled, multiantenna-capable microwave ablation device is safe, with promising treatment effectiveness.
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.. Electronic address: tziemlewicz@uwhealth.org.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Ziemlewicz
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: J Louis
authors.initials: JL
authors.lastname: Hinshaw
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: Meghan G
authors.initials: MG
authors.lastname: Lubner
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.; Department of Biomedical Engineering, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.; Department of Medical Physics, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Brace
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: Marci L
authors.initials: ML
authors.lastname: Alexander
authors.affiliation: Section of Hepatology, Department of Medicine, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: Parul
authors.initials: P
authors.lastname: Agarwal
authors.affiliation: Department of Radiology, University of Wisconsin-Madison, 600 Highland Ave., E3/366 CSC, Madison, WI 53792.
authors.forename: Fred T
authors.initials: FT
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods*; D016461:Chemoembolization, Therapeutic; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008113:Liver Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008872:Microwaves; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome