Usefulness of the preoperative Prognostic Immune and Nutritional Index as a prognostic predictor for patients with gastric cancer.

The Prognostic Immune and Nutritional Index (PINI), integrating albumin and monocyte counts, has emerged as a potential prognostic biomarker in gastrointestinal cancer. The present study aimed to evaluate its predictive value in patients with gastric cancer (GC) undergoing radical gastrectomy. A retrospective cohort study of 82 patients with GC treated at a single institute between January 2016 and December 2019 was conducted. PINI was calculated as [albumin (g/dl) × 0.9]-[monocytes (mm) × 0.0007]. Receiver operating characteristic analysis determined the optimal cutoff (3.075), and patients were stratified into low-PINI (≤3.075; n=33) and high-PINI (>3.075; n=49) groups. Primary outcomes were 5-year recurrence-free survival (RFS) rate and overall survival (OS) rate. The high-PINI group demonstrated significantly higher 5-year RFS (79.6 vs. 51.5%; P<0.001) and OS (85.7 vs. 51.5%; P<0.001) rates compared with the low-PINI group. Multivariate analysis identified PINI ≥3.075 as an independent protective factor for both RFS [hazard ratio (HR), 0.59; 95% confidence interval (CI), 0.38-0.85; P=0.022] and OS (HR, 0.45; 95% CI, 0.25-0.72; P=0.012). Low-PINI patients exhibited more advanced disease characteristics, including higher rates of anemia (39.4 vs. 17.3%; P=0.020), hypoproteinemia (15.2 vs. 0.0%; P=0.005), advanced T stage (75.8 vs. 36.5%; P=0.002), nodal metastasis (63.6 vs. 44.9%; P=0.002) and stage II-III tumors (87.9 vs. 44.9%; P<0.001). In conclusion, preoperative PINI serves as a robust, independent prognostic indicator in GC, effectively stratifying patients by survival outcomes and tumor aggressiveness. The clinical implementation of PINI could enhance risk assessment and guide personalized treatment strategies. Further multicenter studies are warranted to validate these findings.