Application of propensity score method in evaluation on therapeutic effect of primary hepatocellular carcinoma

Objective To analyze therapeutic effects of transcatheter artenial chemoembolization（ TACE） with or without three dimensional conformal radiotherapy（ 3DCRT） in hepatocellular carcinoma（ HCC） patients based on balancing the covariates with propensity score method,and to explore the application of propensity score method. Methods A total of 681 HCC patients treated by TACE（ 339 cases） or TACE + 3DCRT（ 342 cases） were collected from Shandong Tumor Hospital. The propensity score was calculated by logistic regression model and caliper matching was carried out according to the propensity score. And then the matched data were subjected to survival analysis. Results After propensity score matching,age,Child-Pugh grade,vein tumor thrombus,and status of hepatitis B virus surface antigen were balanced. The one-,two-,and three-year survival rate of TACE and TACE + 3DCRT were 65. 4% and 79. 7%,47. 4% and60. 9%,28. 7% and 36. 7% and the median survival time of TACE and TACE + 3DCRT were 1. 672 and 2. 681 year,respectively. Log-rank test showed significant differences in the survival rates berween the two groups（ P = 0. 006）. Conclusion The therapeutic effect of TACE plus 3DCRT is superior to that of TACE. Propensity score method could effectively reduce the confounding bias and make more accurate evaluation on therapeutic effect in HCC patients.