Risk Stratification According to the Prognostic Nutritional Index for Predicting Postoperative Complications After Lung Cancer Surgery

The prognostic nutritional index (PNI), an immune nutritional marker based on serum albumin levels and total lymphocyte count, predicts postoperative complications in various types of malignancies. However, the clinical significance of the PNI for postoperative complications following lung cancer surgery is uncertain. Patients with resected non-small cell lung cancer (n = 515) were retrospectively analyzed and the relationship between the preoperative PNI and postoperative complications was evaluated. Multivariate logistic regression analysis revealed that a preoperative low PNI was a significant independent predictor of postoperative complications of Clavien-Dindo Grade II (odds ratio: 1.06 per unit decrease, 95.0% confidence interval 1.01-1.11). Patients were divided into three groups according to the preoperative PNI: normal ( 50; n = 324), mildly low (< 50, 45; n = 134), and severely low (< 45; n = 57). The incidence of postoperative complications of Grade II and Grade III in the normal, mildly low, and severely low PNI groups was 22.2, 39.6, and 42.1% and 7.1, 16.4, and 22.8%, respectively. The incidence of postoperative complications of Grade II and Grade III was significantly higher in the mildly low and severely low PNI groups than in the normal PNI group (p < 0.001 and p < 0.001, respectively). The incidence of air leak, pneumonia, and extrapulmonary infection, but not arrhythmia, was significantly higher in the mildly low and severely low PNI groups than in the normal PNI group. The PNI could be a useful marker to predict the risk of postoperative complications after lung cancer surgery.