Comparison of the therapeutic efficacy between systemic chemotherapy with and without radiofrequency ablation for colorectal cancer liver metastases: A propensity score matching study.

Abstract

To compare therapeutic efficacy between systemic chemotherapy (SC) alone and preoperative SC followed by radiofrequency ablation (SC+RFA) in patients with colorectal cancer liver metastases (CRLM). This study identified a cohort of patients with CRLM after treatment between 2010 and 2016. Patients who received SC+RFA were compared with SC patients by propensity score matching. Overall survival (OS) and intrahepatic progression-free survival (PFS) were compared using stratified log-rank test. The outcomes after SC and SC+RFA were also assessed in patient subgroups. This study identified 338 patients with CRLM who had underwent SC and had different response to chemotherapy, including non-progressive disease (non-PD) or progressive disease (PD). Of this cohort, 64 patients in SC+RFA group were matched by propensity score to 64 patients who received SC alone. Compared with SC cohort, the SC+RFA cohort yielded better OS (HR, 0.403; 95% CI, 0.271-0.601) and PFS (HR, 0.190; 95% CI, 0.113-0.320). The estimated OS rates at 1, 3 and 5 years were 93.8%, 51.6% and 15.6% for SC+RFA group and 81.3%, 26.6% and 10.9% for SC group (p＜0.001). The cumulative PFS rates at 1, 3, and 5 years were 43.8 %, 14.1% and 3.1% for the SC+RFA group and 1.6%, 0 and 0% for SC group (p＜0.0001). In subgroup analysis, compared with patients with PD response, patients with non-PD response could gain better PFS (HR, 0.207; 95% CI, 0.121-0.354) and OS (HR, 0.390; 95% CI, 0.246-0.617). RFA was associated with improved OS and intrahepatic PFS in CRLM patients with preoperative SC,especially in non-PD response subgroup after SC. The addition of RFA was advocated for CRLM patients with preoperative SC. This study will provide important reference and evidence to better perform the management of unresectable CRLM.