Prognostic immune nutritional index-based nutritional stratification enhances recovery and survival in gastric cancer: A randomized controlled trial

BACKGROUND Postoperative malnutrition, systemic inflammation, and immune dysfunction significantly impair recovery and survival in gastric cancer patients undergoing radical gastrectomy. The Prognostic Immune Nutritional Index (PINI) enables immune-nutritional risk stratification; however, its utility in guiding perioperative nutritional support remains underexplored. AIM To evaluate whether risk-stratified perioperative nutritional support based on PINI scores improves postoperative recovery, quality of life, and long-term outcomes in gastric cancer patients. METHODS In this prospective, randomized controlled trial, 195 patients undergoing radical gastrectomy were stratified into low- (PINI ≤ 1.5), moderate- (1.5 < PINI ≤ 3), and high-risk (PINI > 3) groups. Patients received standard, intensive, or immune-enhancing nutritional support, respectively. Outcomes were assessed at 1 week, 1 month, and 1 year postoperatively and included body mass index (BMI), serum albumin, PINI scores, Pittsburgh Sleep Quality Index (PSQI), Self-Rating Anxiety Scale (SAS), Self-Rating Depression Scale (SDS), Visual Analog Scale (VAS) for pain, EORTC QLQ-C30 for quality of life, complication rates, hospital stay, and survival. RESULTS At 1 year, the high-risk group receiving immune-enhancing nutrition demonstrated the greatest improvements, with higher serum albumin (47.5 ± 3.8 g/L) and stabilized BMI (+0.1 ± 0.2 kg/m2 vs -0.2 ± 0.2 kg/m2 in the low-risk group, P < 0.01). Sleep quality (ΔPSQI: -8.5 ± 2.7), anxiety (ΔSAS: -12.9 ± 3.1), and depression (ΔSDS: -12.6 ± 4.2) improved significantly (all P < 0.01). Pain scores were lowest (VAS: 2.1 ± 1.3), and quality of life was highest (78.2 ± 8.0, P < 0.01). The high-risk group also had the lowest complication rate (3.3%), shortest hospital stay (9.8 ± 2.4 days), and highest 1-year survival (98.5%, P < 0.05). CONCLUSION PINI-based graded nutritional support significantly enhances postoperative recovery, reduces complications, and improves long-term outcomes following radical gastrectomy. These findings support its integration into precision perioperative care strategies for gastric cancer.