Pre-operative Neutrophil-to-lymphocyte Ratio Significantly Predicts Local Recurrence in Pancreatic Ductal Adenocarcinoma

Backgrounds/Aims:Recurrence rates in patients with resected pancreatic ductal adenocarcinoma (PDAC) remain high, posing a significant clinical challenge. Pre-operative neutrophil-to-lymphocyte ratio (NLR) has shown promise as a prognostic marker in various cancers. NLR's role in PDAC recurrence has not been widely explored. This study aims to investigate the effect of pre-operative NLR on post-operative PDAC recurrence. Methods:A retrospective analysis was performed on patients who underwent surgery with curative intent for PDAC between 2015 and 2024. Patients were divided into two groups (high and low) using an NLR threshold of 3. Primary outcome was disease recurrence. The predictive value of NLR was compared using receiver operating characteristic curves and univariable and multivariable Cox regression models. Results:125 Patients were included; high NLR group n = 53 and low NLR group n = 72. Both groups were well balanced across all baseline characteristics. NLR is a strong predictor of recurrence compared to platelet-to-lymphocyte ratio (PLR) (AUC: NLR 0.716 vs. PLR 0.593, p = 0.022). The high NLR group had a significantly greater recurrence rate compared to the low NLR group (62.3% vs. 31.9%, p = 0.002) and a significantly greater local recurrence rate (43.4% vs. 19.4%, p = 0.004). A high NLR remains a significant negative prognosticator for recurrence in univariable (hazard ratio [HR] 2.540, p < 0.001) and multivariable analysis (HR 2.817, p < 0.001). Conclusions:A high pre-operative NLR (> 3) was associated with significantly greater risk of recurrence, especially local recurrence. NLR may be used within risk stratification models to identify patients at risk of PDAC recurrence.