title: Radiofrequency ablation for hepatocellular carcinoma: assistant techniques for difficult cases.
abstract: OBJECTIVE
  To confirm the safety and effectiveness of techniques to assist radiofrequency ablation (RFA) for difficult cases, we retrospectively evaluated successful treatment rates, early complications and local tumor progressions.
  
  
  METHODS
  Between June 1999 and April 2009, a total of 341 patients with 535 nodules were treated as difficult cases. Artificial pleural effusion assisted ablation was performed on 64 patients with 82 nodules. Artificial ascites-assisted ablation was performed on 11 patients with 13 nodules. Cooling by endoscopic nasobiliary drainage (ENBD) tube-assisted ablation was performed on 6 patients with 8 nodules. When the tumors were not well visualized with conventional B-mode ultrasonography (US), contrast-enhanced US-assisted ablation with Levovist or Sonazoid or virtual CT sonography-assisted ablation was performed. Contrast-enhanced US-assisted ablation was performed on 139 patients with 224 nodules and virtual CT sonography-assisted ablation was performed on 121 patients with 209 nodules.
  
  
  RESULTS
  In total, complete ablation was achieved in 514 of 535 (96%) nodules in difficult cases. For RFA with artificial pleural effusion, artificial ascites and ENBD, complete response was confirmed in all cases. For contrast-enhanced US- and CT sonography-assisted ablation, complete response was 95%. Early complications were recognized in 24 cases (4.5%). All cases recovered with no invasive treatment. Local tumor recurrence was investigated in 377 nodules of 245 patients, and 69 (18%) nodules were positive. Tumor recurrences in each assisted technique were 14.7% in artificial pleural effusion cases, 7% in artificial ascites, 12.5% in ENBD tube cases, 31% in virtual CT sonography, and 8.5% in contrast-enhanced US.
  
  
  CONCLUSIONS
  Although local tumor progression needs to be carefully monitored, assisted techniques of RFA for difficult cases are well tolerated and expand the indications of RFA.
authors.affiliation: Department of Gastroenterology and Hepatology, Kinki University School of Medicine, Osaka, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Inoue
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Minami
authors.forename: Hobyung
authors.initials: H
authors.lastname: Chung
authors.forename: Sousuke
authors.initials: S
authors.lastname: Hayaishi
authors.forename: Taisuke
authors.initials: T
authors.lastname: Ueda
authors.forename: Chie
authors.initials: C
authors.lastname: Tatsumi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Takita
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kitai
authors.forename: Kinuyo
authors.initials: K
authors.lastname: Hatanaka
authors.forename: Emi
authors.initials: E
authors.lastname: Ishikawa
authors.forename: Norihisa
authors.initials: N
authors.lastname: Yada
authors.forename: Satoru
authors.initials: S
authors.lastname: Hagiwara
authors.forename: Kazuomi
authors.initials: K
authors.lastname: Ueshima
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kudo
mesh_terms: D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D011379:Prognosis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D018084:Ultrasonography, Interventional