Kras mutational status surpasses the treatment modality in patients with colorectal liver metastases

Abstract

Background: There is little evidence between KRAS mutational status and ablation therapy. The aim of this study is to identify if KRAS mutation has any survival effect on patients undergoing liver ablation therapy and liver resection at a single facility. Methods: Three hundred forty one patients with known K-ras status underwent liver resection (LR) or ablative therapies (AT) for CRLM between 1999 and 2016. All patients were reviewed by a multidisciplinary conference. Patient demographics, clinical and oncological outcome were analyzed. Kaplan Meier and Cox Proportional Hazard model were used to analyze the outcome. Results: Two hundred fifty six patients underwent LR and 85 patients underwent AT. While 225 patients (66.0%) have KRAS wild type tumor (wtKRAS), 116 patients (34.0%) have mutant KRAS tumor (mutKRAS). MutKras group has worse overall survival (OS) than wtKRAS group (median survival 42 months in mutKRAS, 49.5 months in wtKras; p = 0.02).In mutKRAS group, there were no significant difference in OS between patients with LR and AT (median survival 39.3 months in AT, 42.5 months in LR; p = 0.64) in comparison to wtKRAS group (median survival 35.2 months in AT, 53.6 months in LR; p = 0.01). After controlling KRAS mutational status, the number of liver metastases is an independent risk factor for survival in both wtKRAS and mutKRAS groups on Cox Proportional Hazard model (HR 1.83, 95%CI 1.16–2.98, p = 0.01, HR 1.98, 95%CI 1.10–3.69, p = 0.02). Conclusion: The treatment modality, either liver resection or ablation, has no impact for OS in patients with KRAS mutation.