Background: Surgery for hepatocellular carcinoma (HCC) had great improvements in the last decades with low morbidity and mortality and good long-term results. Percutaneous local ablative therapies (LAT) such as radiofrequency ablation and ethanol injection (PEI) for HCC gained consent for their efficacy and safety. In retrospective studies, patients submitted to resection (LR) or LAT frequently have important selection bias. Propensity case-matched analysis proved to reduce selection bias of retrospective studies and allow comparison between different therapies.
Aim: The aim of this study was to evaluate survival comparing LR and LAT in two groups of cirrhotic patients with HCC matched with propensity score methods.
Methods: Four hundred and seventy-eight cirrhotic patients with HCC treated with LR or LAT with curative intent between January 1995 and December 2009 were included in the study. One hundred and eighty-one patients underwent LR, and 297 patients were treated with LAT. Tumor stage and liver function were evaluated in all patients. To balance the covariates in the two groups, a one-to-one propensity case-matched analysis was used. A multivariable logistic model based on age, gender, etiology of cirrhosis, Child-Pugh class, number of nodules, maximum diameter of nodules, and serum alpha-fetoprotein level was used to estimate propensity score. One-to-one caliper matching of LR and LAT groups was performed, generating a matched sample of 176 patients with 88 patients in each group.
Results: Median survival was 65.1 months (95% CI = 48.5-81.7) after LR and 37.3 months (95% CI = 29.3-45.3) after LAT (p = 0.008). For patients in Child-Pugh class A with single HCC and maximum diameter <5 cm, median survival was 65.0 months (95% CI = 58.4-71.6) for the LR group and 63.7 months (95% CI = 31.8-95.7) for the LAT group (p = 0.730). For patients in Child-Pugh class A with single HCC and diameter ≥5 cm, median survival was 79.9 months (95% CI = 40.1-119.8) for the LR group and 21.5 months (95% CI = 10.8-32.1) for the LAT group (p = 0.023). For patients in Child-Pugh class A with two to three nodules and maximum diameter ≤3 cm, mean survival was 69.3 months (95% CI 48.7-89.9) for the LR group and 45.7 months (95% CI = 22.8-68.7) for the LAT group (p = 0.168). For patients in Child-Pugh class A with two to three nodules and diameter >3 cm, median survival was 82.9 months (95% CI = 52.0-113.7) for the LR group and 18.9 months (95% CI = 6.3-31.4) for the LAT group (p = 0.001).
Conclusion: Our propensity case-matched study confirmed that survival is similar after LR and LAT for single HCC smaller than 5 cm and for oligofocal HCC (up to three nodules) smaller than 3 cm; instead, for HCC larger than 5 cm or oligofocal HCC (up to three nodules) larger than 3 cm, surgical resection improves significantly long-term survival.