Impact of the prognostic nutritional index on the recovery and long-term oncologic outcome of patients with colorectal cancer.

Abstract

The prognostic nutritional index (PNI) has been reported to be a predictive marker for surgical outcomes and prognosis in gastrointestinal malignancies. In this study, we aimed to identify the impact of preoperative PNI on the recovery and long-term oncologic outcome of patients with colorectal cancer (CRC). A total of 3569 patients who underwent curative resection for CRC were enrolled, and their medical records were analyzed retrospectively. Preoperative PNI was calculated as 10× serum albumin concentration (g/dL) + 0.005 × total lymphocyte count (/mm3). The occurrence of postoperative complications, duration of hospital stay, disease-free survival, and overall survival were analyzed according to the preoperative PNI. In addition, PNI was compared according to the status of pathologic factors. The postoperative complication rate and postoperative duration of hospital stay increased significantly as PNI increased. Patients with a lower PNI showed a worse survival outcome. Increased depth of tumor invasion, presence of distant metastasis, and poorer histologic grade were associated with a lower PNI. The cut-point of preoperative PNI was calculated as 50, and patients with PNI > 50 showed a markedly better survival outcome. Furthermore, patients with PNI > 50 showed better results in postoperative complication rate and postoperative duration of hospital stay. Preoperative PNI is a simple and efficient indicator (cut-point 50) for estimating the recovery and oncologic outcome of patients. A low PNI was associated with increased occurrence of postoperative complications, prolonged hospital stay, poor oncologic outcome, and aggressive tumor phenotypes.