title: Percutaneous radiofrequency ablation of hepatocellular carcinoma: effect of histologic grade on therapeutic results.
abstract: OBJECTIVE
  The purpose of our study was to assess the therapeutic results of radiofrequency ablation of hepatocellular carcinoma (HCC) based on the histologic grades of the tumors.
  
  
  METHODS
  Between April 1999 and December 2003, 95 patients with nodular HCC were treated with percutaneous radiofrequency ablation. All tumors were histologically proven by sonography-guided percutaneous biopsy and were classified as Edmondson-Steiner grade I HCC (n = 38) (mean, 2.3 cm) (group 1), grade II HCC (n = 50) (mean, 2.4 cm) (group 2), or grade III HCC (n = 7) (mean, 2.8 cm) (group 3). All patients underwent contrast-enhanced three-phase helical CT examination before and after radiofrequency ablation. After retrospective review of the medical records and follow-up CT examinations, the rates of technique effectiveness, local tumor progression, cumulative survival, and cancer-free survival using a Kaplan-Meier method were calculated and compared among the groups.
  
  
  RESULTS
  Technique effectiveness rates in groups 1, 2, and 3 were 87% (27/31), 71% (30/42), and 43% (3/7), respectively, with statistical significance (p = 0.032). Local tumor progression rates in groups 1, 2, and 3 were 16% (5/31), 36% (15/42), and 71% (5/7), respectively, with statistical significance (p = 0.013). Five-year cumulative survival rates in groups 1, 2, and 3 were 71%, 44%, and 43%, respectively, with no statistical significance (p > 0.05). Four-year cancer-free survival rates in groups 1, 2, and 3 were 39%, 10%, and 0%, respectively (p < 0.05 for groups 1 vs 2; p > 0.05 for groups 1 vs 3 and groups 2 vs 3).
  
  
  CONCLUSIONS
  The histologic grade of HCC is an important factor influencing therapeutic results with survival after radiofrequency ablation.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-ku, Seoul 135-710, South Korea.
authors.forename: Seong Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Hyo K
authors.initials: HK
authors.lastname: Lim
authors.forename: Dongil
authors.initials: D
authors.lastname: Choi
authors.forename: Won Jae
authors.initials: WJ
authors.lastname: Lee
authors.forename: Seung Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Min Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Chan Kyo
authors.initials: CK
authors.lastname: Kim
authors.forename: Yong Hwan
authors.initials: YH
authors.lastname: Jeon
authors.forename: Jong Mee
authors.initials: JM
authors.lastname: Lee
authors.forename: Hyunchul
authors.initials: H
authors.lastname: Rhim
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015996:Survival Rate; D016896:Treatment Outcome