Poor prognosis in patients with resectable KRAS-MUT colorectal liver metastases is improved by adjuvant hepatic arterial infusion chemotherapy.

Abstract

e15161 Background: Patients with KRAS-mutated colorectal cancer liver metastases (CRLM) have worse outcomes after resection. Adjuvant hepatic artery pump chemotherapy (HAIC) improves overall survival. We investigated the impact of HAIC in relation to KRAS mutational status in patients with resected CRLM. Methods: Patients with resected CRLM treated with and without adjuvant HAIC and available KRAS status (wild-type, WT; mutated, MUT) were reviewed from a prospective institutional database. Correlations between KRAS status, adjuvant HAIC, clinical factors, and overall survival (OS) were analyzed. Cox proportional hazard model was used to adjust for confounders. Results: Between 1993-2012, 675 patients (419 KRAS-WT, 256 KRAS-MUT) with a median follow up of 6.5 years after resection were evaluated. Fifty-four percent received adjuvant HAIC. Tumor characteristics (synchronous disease, number of lesions, clinical-risk score, 2-stage hepatectomy) were significantly worse in the HAIC group, however, there were more patients with extrahepatic metastases in the no-HAIC group. Adjuvant HAIC was associated with improved OS in both KRAS-WT (5-yr OS 76% vs 57%, HR 0.51, p<0.01) and KRAS-MUT (5-yr OS 59% vs 40%, HR 0.56, p<0.01) patients. On multivariate analysis, HAIC remained associated with improved OS (HR 0.6, p<0.001) independent of KRAS status and other clinico-pathologic factors. Conclusions: Adjuvant HAIC after resection of CRLM is independently associated with improved OS regardless of KRAS status and may abrogate the poor prognosis in resectable KRAS-MUT CRLM. [Table: see text]