title: Early diffuse recurrence of hepatocellular carcinoma after percutaneous radiofrequency ablation: analysis of risk factors.
abstract: OBJECTIVE
  To evaluate the risk factors affecting early diffuse recurrence within 1 year of percutaneous ultrasound-guided radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).
  
  
  METHODS
  Out of 146 patients who received transcatheter arterial chemoembolisation (TACE) for treatment of recurrent HCC after percutaneous ultrasound-guided RFA, we selected 23 patients with early diffuse recurrence. Early diffuse recurrence was defined as three or more new recurrent HCCs within 1 year of initial RFA. As a control group, we selected 23 patients, matched exactly for age and sex, in which there was no local tumour progression or new recurrence after RFA. To analyse the risk factors, we examined patient factors and tumour factors.
  
  
  RESULTS
  Recurrent tumours occurred from 30 to 365 days after RFA (median time, 203 days). Univariate analysis indicated that larger tumour size and poorly defined margin were significant risk factors (P < 0.05). Multivariate analysis indicated that poorly defined margin was a significant risk factor (P < 0.05).
  
  
  CONCLUSIONS
  Larger tumour size and poorly defined margin may be risk factors for early diffuse recurrence of HCC within 1 year of RFA. Tumours with such risk factors should be treated with a combination of TACE to minimise the potential for therapeutic failure.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunwan University, School of Medicine, 50 Ilwon-dong, Gangnam-gu, Seoul, 135-710, Korea.
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Lee
authors.forename: Hyunchul
authors.initials: H
authors.lastname: Rhim
authors.forename: Min Woo
authors.initials: MW
authors.lastname: Lee
authors.forename: Young-Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Dongil
authors.initials: D
authors.lastname: Choi
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Park
authors.forename: Young Kon
authors.initials: YK
authors.lastname: Kim
authors.forename: Seong Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Hyo Keun
authors.initials: HK
authors.lastname: Lim
mesh_terms: D000368:Aged; D001706:Biopsy; D006528:Carcinoma, Hepatocellular / Q000601:surgery*; D016022:Case-Control Studies; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D018450:Disease Progression; D005260:Female; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D008113:Liver Neoplasms / Q000601:surgery*; D008297:Male; D009364:Neoplasm Recurrence, Local; D016016:Proportional Hazards Models; D012307:Risk Factors; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide