Significance and prognostic factors in 84 patients with colorectal liver metastases treated with radiofrequency ablation

Abstract

To investigate the prognostic factors and significance of patients with colorectal liver metastases (CLM) treated with radiofrequency ablation (RFA). A retrospective study was conducted for the clinic outcomes, follow-up data and survival status in 84 patients with CLM undergoing RFA between January 2000 and December 2008. Univariate and multivariate analyses were performed by log-rank test and Cox's proportional hazard model respectively. A total of 265 lesions in 84 patients received RFA with a follow-up of 1-10 years. The median survival was 29 months, 1-year survival rate 98%, 3-year survival rate 27% and 5-year survival rate 7%. For those lesion < or = 4 cm and lesion number < 3, the median survival time was 30 months, 1-year survival rate 100%, 3-year survival rate 31% and 5-year survival rate 16%. For those with lesions > 4 cm or lesion number > 3, the median survival time was 28 months, 1-year survival rate 96%, 3-year survival rate 21% and 5-year survival rate 0. For those receiving RFA combined with chemotherapy, the median survival time was 32 months, three-year survival rate 29% and five-year survival rate 8%. For those on molecular-target therapy, the median survival time was 41 months, 3-year survival rate 60% and 5-year survival rate 20%. The multivariate statistical analysis showed that the influences of lesion number and size (P = 0.004), chemotherapeutic agents and timing (P = 0.004) and extra-liver metastases (P = 0.097) had statistic significance to the survival rate. RFA has a favorable outcome in the treatment of CLM patients. The prognostic factors of overall survival are correlated with the lesion size and presence or absence of extra-hepatic metastasis. It may effectively improve the patient prognosis by RFA in combination with chemotherapy and especially molecular-target therapy.