Anatomical Resections Improve Relapse-Free Survival in Patients with KRAS/NRAS/BRAF- Mutated Colorectal Liver Metastases

Background The type of liver resection (anatomical resection, AR or nonanatomical resection, NAR) for colorectal liver metastases (CRLM) is subject to debate. The debate may persist because some certain prognostic implications, associated with worse biological behavior of tumors, have been overlooked. The aim of this study was to explore the characteristics of patients who would benefit more from the performance of AR. Methods 475 patients who underwent hepatic resection of CRLM were included and stratified by KRAS/NRAS/BRAF mutational status. The Kaplan-Meier method was applied in relapse-free survival (RFS), and the Cox proportional hazards model was used to identify independent predictors of prognosis in multivariable analysis. Results Among all 475 patients, 154 (32.4%) underwent AR and 321 (67.6%) underwent NAR. 1-, 2-, and 3-year RFS for the entire cohort were 63.0%, 40.6%, and 31.2% respectively. In the cohort of patients with KRAS/NRAS/BRAF mutated tumors, patients who underwent AR had a markedly improved median RFS compared with patients who underwent NAR (24.1 VS. 12.9 months, P = 0.005). Upon the multivariable analyses, the performance of AR (hazard ratios=0.562; 95% CI 0.370-0.854, P = 0.007) remained prognostic independently for a superior RFS. In contrast, in the cohort of patients with KRAS/NRAS/BRAF wild-type tumors, patients who underwent AR had a comparable median RFS compared with those who underwent NAR (24.9 VS. 20.3 months, P = 0.901). Conclusions Patients with KRAS/NRAS/BRAF mutated tumors may benefit more from the performance of AR than from the performance of NAR. Legal entity responsible for the study Zhongshan Hospital. Funding The National Natural Science Foundation of China. Disclosure All authors have declared no conflicts of interest.