Novel Somay's GLUCAR index efficiently predicts survival outcomes in locally advanced pancreas cancer patients receiving definitive chemoradiotherapy: a propensity-score-matched cohort analysis

Abstract

Background: Propensity score matching (PSM) was used to investigate the prognostic value of a novel GLUCAR index [Glucose x (C-reactive protein divided by albumin)] in unresectable locally advanced pancreatic cancer (LA-NPC) patients who received definitive concurrent chemoradiotherapy (CCRT). Methods: The PSM analysis comprised 142 LA-PAC patients subjected to definitive CCRT. Receiver operating characteristic (ROC) curve analysis was utilized to identify relevant pre-CCRT cutoffs that could effectively stratify survival results. The primary and secondary objectives were the correlations between the pre-CCRT GLUCAR measures and overall survival (OS) and progression-free survival (PFS). Results: The ROC analysis revealed significance at 43.3 for PFS [area under the curve (AUC): 85.1%;sensitivity: 76.8%;specificity: 74.2%;J-index: 0.510)] and 42.8 for OS (AUC: 81.8%;sensitivity: 74.2%;specificity: 71.7%;J-index: 0.459). Given that these cutoff points were close, the standard cutoff point, 42.8, was selected for further analysis. Comparative survival analyses showed that pre-CCRT GLUCAR >= 42.8 (n = 71) measures were associated with significantly shorter median PFS (4.7 vs. 15.8 months;p < 0.001) and OS (10.1 vs. 25.4 months;p < 0.001) durations compared to GLUCAR < 42.8 measures (n = 71). The multivariate analysis results confirmed the independent significance of the GLUCAR index on PFS (p < 0.001) and OS (p < 0.001) outcomes. Conclusions: Elevated pre-CCRT GLUCAR levels are robustly and independently linked to significantly poorer PFS and OS outcomes in unresectable LA-PAC patients treated with definitive CCRT.