title: Conditional survival analysis of hepatocellular carcinoma patients treated with radiofrequency ablation.
abstract: OBJECTIVE
  Survival estimates are commonly reported as survival from the first observation, but future survival probability changes based on the survival time already accumulated after therapy, otherwise known as conditional survival (CS). The aim of the study was to describe CS according to different prognostic variables in hepatocellular carcinoma (HCC) patients treated with radiofrequency ablation (RFA).
  
  
  METHODS
  Data on 125 very early/early HCC patients treated with RFA between 1999 and 2007 were analyzed. Actuarial survival estimates were computed by means of Kaplan-Meier method and compared by log-rank test. The 5-year CS was calculated with stratification by several predictors for patients who had already survived up to 5 years from diagnosis.
  
  
  RESULTS
  Median overall survival (OS) was 72 months (95% confidence interval [CI], 58-86). Age, Child-Pugh (CP), α-fetoprotein (AFP), Cancer of the Liver Italian Program (CLIP) score and type of recurrence (early vs late) were significant predictors of OS. The 5-year CS rates of the entire study cohort assessed at 1, 2, 3 and 5 years from the treatment were 49%, 48%, 30% and 34%, respectively. Subgroup analysis confirmed age and CP as significant predictors of CS at all time points, while the CS of subgroups stratified by AFP and CLIP did not differ significantly from the 3rd year after RFA onward, as more advanced patients had probably escaped early recurrence.
  
  
  CONCLUSIONS
  CS analysis showed that the impact of different variables influencing OS is not linear over time after RFA. Information derived from the study can improve the current management of HCC patients.
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Facciorusso
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Del Prete
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Antonino
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: Neve
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Annabianca
authors.initials: A
authors.lastname: Amoruso
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Crucinio
authors.affiliation: Gastroenterology Unit, Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Di Leo
authors.affiliation: Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, Ospedali Riuniti Foggia, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Barone
keywords: cancer; cirrhosis; hepatocellular carcinoma; radiofrequency ablation