Preoperative Prognostic Nutritional Index Predicts Long-term Outcomes After Curative Gastrectomy for Gastric Cancer

Background/Aim: Although the incidence of gastric cancer has been declining worldwide, it remains a major cause of cancer-related mortality. Given the invasive nature of gastrectomy, perioperative nutritional status may critically influence postoperative recovery and long-term outcomes. This study aimed to investigate the prognostic impact of the preoperative prognostic nutritional index (PNI) on long-term outcomes after curative gastrectomy for gastric cancer. Patients and Methods: This retrospective cohort study analyzed 901 consecutive patients who underwent curative gastrectomy, including distal gastrectomy (DG), total gastrectomy (TG), or proximal gastrectomy (PG), between 2009 and 2020. PNI was calculated using a standard formula, and patients were stratified into high-PNI (≥45) and low-PNI (<45) groups. Overall survival (OS) and recurrence-free survival (RFS) were compared using Kaplan–Meier analysis and Cox proportional hazards models. Results: Baseline clinicopathological characteristics were compared between the low- and high-PNI groups. The 5-year OS rates were 84.3% in the high-PNI group and 64.1% in the low-PNI group (p<0.001). The 5-year RFS rates were 88.4% and 81.3%, respectively (p=0.005). In multivariable Cox proportional hazards analysis, low preoperative PNI was independently associated with poorer OS [hazard ratio (HR)=1.81, 95% confidence interval (CI)=1.31-2.51, p<0.001] and RFS (HR=1.69, 95%CI=1.24-2.32, p=0.001). Subgroup analyses showed no statistically significant interaction between PNI and surgical approach. Conclusion: Preoperative PNI is a useful predictor of long-term outcomes after curative gastrectomy for gastric cancer and may facilitate risk stratification and individualized perioperative management.