Association of Preoperative Lymphocyte-to-Monocyte Ratio with Failure to Achieve Textbook Outcome After Pancreatoduodenectomy for Pancreatic and Periampullary Cancer.

INTRODUCTION: Pancreatoduodenectomy (PD) is associated with substantial morbidity, underscoring the need for preoperative risk stratification. This study evaluated whether objective, partially modifiable, preoperative host factors, including aerobic fitness, body composition, and immunonutritional biomarkers, are associated with failure to achieve textbook outcome (TO) after PD. MATERIALS AND METHODS: This retrospective cohort study included patients with malignant pancreatic or periampullary tumors, who performed a routine cardiopulmonary exercise test (CPET) and underwent PD. Body composition was analyzed with CT. Immunonutritional biomarkers included lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), prognostic nutritional index (PNI) and CRP-to-albumin ratio (CAR). TO was defined as the absence of postoperative pancreatic fistula (POPF), bile leak, post-pancreatectomy hemorrhage, major complications, 30-day readmission and 30-day mortality. RESULTS: In total, 105 patients were included, of whom 47 patients (44.8%) failed to achieve TO. Compared with the TO group, non-TO patients were older (70.2 ± 7.8 vs. 66.8 ± 9.0 years), had higher PLR (194.9 [147.3-274.1] vs. 162.8 [105.5-224.6], p = 0.016) and lower LMR (2.1 [1.4-3.2] vs. 2.9 [1.9-4.2], p = 0.005). Aerobic fitness, body composition, and other biomarkers did not differ significantly. In multivariable analysis, LMR (OR 0.588, 95%-CI 0.406-0.853, p = 0.005) and risk of POPF (OR 3.410 for intermediate risk (95%-CI 1.184-9.817, p = 0.023) and OR 3.877 for high risk (95%-CI 1.310-11.473, p = 0.014) compared to low risk) were independently associated with failure to achieve TO. CONCLUSIONS: Lower LMR adjusted for higher fistula risk score independently predicts failure to achieve TO after PD. Preoperative LMR may serve as a simple, objective predictor and a potential target for preoperative optimization.