The Impact of KRAS Mutational Status on Long-Term Survival following Liver Resection for Hilar Cholangiocarcinoma

SIMPLE SUMMARY: The reported frequency of KRAS mutations and their prognostic impact in patients resected for hilar cholangiocarcinoma are controversial. The aim of this study was to evaluate the rate of KRAS mutations in a single-center homogeneous population resected for hilar cholangiocarcinoma and the impact on prognosis. The frequency of KRAS mutations was 22.2%. KRAS mutation was not related with pathologic characteristics of the tumor. Patients with a KRAS mutation presented zero 5-year OS that was significantly lower than that observed in patients with KRAS wild type (5-year OS = 49.2%, p = 0.003). In the multivariable analysis, KRAS mutation was an independent strong predictor of poor OS. KRAS mutation analysis should be included in the routine pathologic evaluation of resected hilar cholangiocarcinoma in order to better stratify prognosis. ABSTRACT: KRAS mutation is reportedly associated with poor prognosis in patients with different cancer types. However, mutational data on hilar cholangiocarcinoma are few and controversial. The aim of this study was to evaluate the rate of KRAS mutations in a single-center homogeneous population resected for hilar cholangiocarcinoma and the subsequent impact on prognosis. KRAS mutation status was evaluated in 54 patients undergoing major hepatectomy combined with resection of the main biliary confluence and regional lymphadenectomy for hilar cholangiocarcinoma between 2001 and 2019. Among these 54 patients, 12 (22.2%) had a KRAS mutation. KRAS mutation was not related with pathologic characteristics of the tumor. Five-year overall survival (OS) in patients with KRAS mutation was significantly lower than that observed in patients with KRAS wild type (0 vs. 49.2%, respectively; p = 0.003). In the multivariable analysis; independent predictors of poor OS were KRAS mutation (HR = 5.384; p = 0.003) and lymph node metastases (HR = 2.805; p = 0.023). The results of our study suggested that KRAS mutation in hilar cholangiocarcinoma was not rarely observed. KRAS mutation was an independent strong predictor of poor OS. KRAS mutation analysis should be included in the routine pathologic evaluation of resected hilar cholangiocarcinoma in order to better stratify prognosis