Fong's Score in the Era of Modern Perioperative Chemotherapy for Metastatic Colorectal Cancer: A Post Hoc Analysis of the GERCOR-MIROX Phase III Trial.

Abstract

Despite improvement in colorectal liver metastasis (CLM) treatment, survival after liver surgery remains highly variable. Several clinicopathologic prognostic factors have been reported, but their validity in the era of more effective perioperative chemotherapy remains to be defined. The aim of this study is to analyze the prognostic factors associated with survival after CLM resection. Clinicopathologic data of patients included in the MIROX phase III trial who underwent surgery for isolated CLMs were analyzed. The primary endpoints were 5-year overall survival (OS) and disease-free survival (DFS). Univariate Cox analysis was performed to identify associations with OS and DFS and select variables for inclusion in a multivariate model to determine their independent prognostic value. A total of 181 patients were analyzed. The median follow-up period was 6.42 years [95% confidence interval (CI) 5.15-8.71 years], and the 5-year OS and DFS rates were 67.1% and 35.4%, respectively. On multivariate analysis, Fong's clinical risk score (CRS) as a categorical variable (CRS 0-1 vs. 2-3 vs. 4-5, p = 0.036) and polymorphonuclear neutrophil (PMN) count (> 6000/mm³ vs. ≤ 6000/mm³, p = 0.006) before chemotherapy were found to be independent prognostic factors for OS. However, only Fong's CRS remained significantly associated with DFS (p = 0.027). The final OS model was used to establish a nomogram that allows individual OS estimations at 1, 3, 5, and 10 years. Fong's CRS was independently associated with DFS and poor OS after CLM resection with FOLFOX-based chemotherapy regimen. It could be useful in daily practice and future trials to select patients more accurately.