Abstract
Hepatectomy and/or local ablation therapy have been recommended for colorectal cancer liver metastases (CRLM). However, they still lack strong evidence for their survival benefits, in addition to systemic therapy. This study aims to evaluate the survival evidence of hepatectomy and/or radiofrequency ablation (RFA) therapy in CRLM patients from a large multi-institutional database. A total of 20,251 patients with colorectal cancer, 4521 of whom were with CRLM, were screened for eligibility. Finally, 2612 patients (637 hepatectomy, 93 RFA, 92 combined hepatectomy and RFA, and 1790 non-aggressive treatment) were enrolled. Frequency matching analysis was used to adjust for baseline differences. The 5-year overall survival (OS) was as follows: hepatectomy alone was 47.8%, combined hepatectomy plus RFA was 35.9%, RFA alone was 29.2%, and the non-aggressive treatment group was 7.4%. Kaplan-Meier curves showed that hepatectomy, RFA, and combination were significantly associated with a better OS compared to those without aggressive local therapy (p < 0.001). Multivariate Cox regression analysis showed that male gender (hazard ratio (HR) 0.89; 95% confidence interval (CI), 0.81-0.97; p = 0.011), old age (≥60 years) (HR 1.20; 95% CI, 1.09-1.32; p < 0.001), high CEA level (>5 ng/mL) (HR 2.14; 95% CI, 1.89-2.42; p < 0.001), primary right-sided cancer (HR 1.35; 95% CI, 1.22-1.51; p < 0.001), extrahepatic metastasis (HR 1.46; 95% CI, 1.33-1.60; p < 0.001), systemic therapy (HR 0.7; 95% CI, 0.62-0.79; p < 0.001), and aggressive local therapy (hepatectomy vs. non-local therapy HR 0.22; 95% CI, 0.20-0.26; p < 0.001; RFA vs. non-local therapy HR 0.29; 95% CI, 0.29-0.41; p < 0.001) were independent factors associated with OS. In the frequency matching analysis, patients receiving hepatectomy and/or RFA resulted in a better OS than those without (p < 0.001). In conclusion, aggressive local treatment provides survival advantages over systemic therapy alone among CRLM patients.