Abstract:

To study the effects of radiofrequency ablation (RFA) and percutaneous ethanol injection（PEI）on  early-stage hepatocellular carcinoma (HCC) patients and to clarify the significance of balancing covariates between groups. Methods 342 HCC patients were selected,in which  189 patients were treated with RFA(RFA group) and 153 patients were treated with  PEI(PEI group). The covariates in two groups were balanced by propensity score caliper matching,and the survival rates of patients in two groups were analyzed. Results Before matching of propensity score,the  covariates in two groups were imbalanced.The COX regression results showed that high Chlid-pugh,family history with HCC,positive HbsAg,high AFP and GT levels,bigger tumor size and multiple nodules were the dangerous factors which could affect the mortality rates of HCC patients(harzard ratio>1,P<0.05);but the difference of mortality rates between two groups was not statistically significant (P>0.05). After matching of propensity score,the covariates were balanced; the survival analysis result showed that the one-year survival rates of patients in RFA and PEI groups were 81.37% and 3.48%,respectively;the two-year survival rates were 46.64% and 36.81%,respectively;the three-year survival rates were 21.53% and 14.5%,respectively;and the median survival time were 1.80 and 1.40 year,respectively.The Logrank test results showed that the survival rates of patients in RFA group were higher than those in PEI group(P<0.05). Conclusion The effect of RFA in treatment of HCC is better than that of PEI after balancing covariates with propensity score,  and balancing covariates between groups can evaluate the curative effect of HCC patients correctly.

Key words: radiofrequency ablation;percutaneous ethanol injection;propensity score;matching method;hepatocellular carcinoma;survival analysis