Abstract
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/m(2) vs -0.2 ± 0.2 kg/m(2) 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.