Impact of perioperative prognostic nutritional index changes on the survival of patients with stage II/III colorectal cancer

Aim: To assess the impact of perioperative prognostic nutritional index (PNI) changes on prognosis and recurrence after colorectal cancer surgery.

Methods: A total of 475 patients who underwent curative resection for primary colorectal adenocarcinoma and were diagnosed with pathological stage (pStage) II/III were retrospectively reviewed. The patients were divided into two groups: the high group (preoperative PNI ≤ postoperative PNI, n = 290) and the low group (preoperative PNI > postoperative PNI, n = 185).

Results: The low group exhibited significantly higher recurrence and mortality rates (all p < 0.001). Kaplan-Meier analysis showed worse overall and recurrence-free survival in the low group (all p < 0.001). Perioperative PNI changes predicted prognosis and recurrence independent of preoperative nutritional conditions. Subgroup analyses showed better overall survival and recurrence-free survival in the high group across various parameters, such as patient background, surgical outcomes, adjuvant chemotherapy, and pathological characteristics. Multivariate analysis revealed that the low group based on perioperative PNI changes (hazard ratio [HR]: 5.809, 95% confidence interval [CI]: 3.451-9.779, p < 0.001), pathological T stage (HR: 1.962, 95% CI: 1.184-3.253, p = 0.009), and pathological N stage (HR: 3.434, 95% CI: 1.964-6.004, p < 0.001) were identified as independent predictors of worse overall survival.

Conclusions: Patients with pStage II/III colorectal cancer who demonstrate a lower postoperative PNI levels compared to preoperative had poorer overall survival and recurrence-free survival. Perioperative PNI changes can serve as useful biomarkers for predicting survival and recurrence.