Predictive role of the prognostic nutritional index in patients with pancreatic ductal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by curative pancreatic resection: A retrospective study using prospectively collected data

Background: Despite a strong association between nutritional indices and disease prognosis, evidence regarding the evaluation of nutritional indices after preoperative treatment for pancreatic ductal adenocarcinoma (PDAC) is insufficient. We evaluated the clinical significance of the prognostic nutritional index (PNI) in patients with resectable (R-) and borderline resectable (BR-) PDAC who received neoadjuvant chemoradiotherapy (NACRT) followed by pancreatic resection. Methods: We assessed 153 patients with R- and BR-PDAC who underwent NACRT followed by curative resection between 2009 and 2022. We evaluated the association between preoperative PNI after NACRT and short- and long-term outcomes. Results: The median preoperative PNI value after NACRT was 42.1, and the optimal cutoff value from the time-dependent receiver operating characteristic curve was 38.6. The low PNI group (PNI < 38.6, n = 44) exhibited significantly worse inflammatory parameters, surgical outcomes, and prognoses than the high PNI group (PNI >= 38.6, n = 109). Multivariate analysis identified preoperative PNI <= 38.6 (hazard ratio [HR]: 2.32, 95% confidence interval [CI]: 1.00-5.38, p = .049), blood loss >= 1642 mL (HR: 3.05, 95% CI: 1.65-5.64, p < .001), node positive pathology (HR: 2.10, 95% CI: 1.32-3.34, p = .002), and lack of postoperative adjuvant chemotherapy (HR: 3.55, 95% CI: 2.05-6.15, p < .001) as significant predictors of overall survival. Conclusions: For patients with R- and BR-PDAC receiving preoperative treatment, it is imperative to closely monitor their nutritional status when determining the optimal surgical procedure timing.