A novel combined carbohydrate antigen 19-9 and lymphocyte-to-monocyte ratio score can predict early recurrence of resectable pancreatic ductal adenocarcinoma

Purpose: Pancreatic ductal adenocarcinoma (PDAC) often recurs early after radical resection, which causes a poor prognosis. This study aimed to establish a scoring model to assess the optimal treatment in patients who underwent surgery for PDAC. Methods: This single-center retrospective study included 127 patients who underwent radical resection for PDAC between 2005 and 2021. Early recurrence (ER) was defined as recurrence within 12 months after resection. The predictive effect for ER was evaluated using receiver operating characteristic (ROC) curves of preoperative parameters. Results: ER occurred in 43 (33.9%) patients. The ER group had a significantly worse prognosis than the non-ER group (p < 0.0001). The carbohydrate antigen 19-9 (CA19-9) level and lymphocyte-to-monocyte ratio (LMR) were the strongest diagnostic factors (areas under the ROC curves: 0.74 and 0.68, respectively). The ER prediction score was calculated using optimal cutoff values. A higher CA19-9-LMR score was associated with a worse prognosis in terms of the overall and recurrence-free survival (p = 0.0017 and p < 0.0001, respectively). A multivariate analysis identified a high CA19-9-LMR score as an independent predictor of ER. Conclusions: The CA19-9-LMR scoring model can predict ER after surgery and is applicable for risk stratification in the assessment of patients with resectable PDAC.