Combined hepatic resection and radio-frequency ablation for patients with colorectal cancer liver metastasis: A viable option for patients with a large number of tumors

Background/Aim: Radiofrequency ablation (RFA) is thought to result in inferior prognosis than hepatic resection among patients with colorectal liver metastasis (CRLM). However, resection plus RFA may be an option for patients with a large number of tumors (≥4 liver lesions) and borderline resectability. Materials and Methods: A total of 717 patients with CRLM who underwent hepatic resection +/- RFA at two tertiary institutions between 09/01/2000-12/01/2015 were eligible for inclusion in this study. Results: Among patients with <4 lesions (n=568), OS in the resection + RFA group (n=48) was significantly worse than in the resection alone group (n=520) (5-year OS: 34.4 % versus 58.9%, p=0.007). Conversely, in patients with ≥4 lesions, OS in the resection + RFA (n=68) and resection alone(n=81) groups were not significantly different (5-year OS: 31.9% versus 34.1%, p=0.48). In patients with <4 lesions, carcinoembryonic antigen (CEA) ≥30 ng/ml, extrahepatic metastasis, preoperative chemotherapy and resection + RFA were independently associated with poor prognosis. Interestingly, in patients with ≥4 lesions, positive primary lymph nodes, KRAS mutation, CEA ≥30 ng/ml and extrahepatic metastasis were independent predictors of poor prognosis; however, the combination of hepatic resection with RFA was not associated with worse survival (p=0.93). Conclusion: Although surgeons should always strive for R0 resection when feasible, combined resection and RFA may be a viable alternative for CRLM patients with a large number of tumors.