Preoperative Prognostic Nutritional Index is a Significant Predictor of Survival in Renal Cell Carcinoma Patients Undergoing Nephrectomy

Preoperative assessment of patients' immunologic and nutritional conditions is required to predict the outcome of patients with malignant tumors. The aim of the current study was to clarify the significance of the prognostic nutritional index (PNI), which simply accounts for immunological and nutritional conditions, in patients with renal cell carcinoma (RCC). We included 1437 patients who underwent nephrectomy for RCC between 1994 and 2008. PNI was calculated using the following formula: 10 x serum albumin concentration (g/dL) + 0.005 x lymphocyte counts (number/mm(2)) in peripheral blood. We examined the correlation of the preoperative PNI value with clinicopathological features. A Cox regression model and the Harrell concordance index with variables only or combined PNI data were used to evaluate the prognostic significance in the T1-4NallMall and T1-4N0M0 groups. The mean preoperative PNI value was 52.7 +/- A 6.3 (range 27.7-85.3). The mean PNI values were significantly lower in patients with more advanced tumor T stage, regional lymph node metastasis, distant metastases, higher Fuhrman grade, and sarcomatoid differentiation than in patients without such factors (p < 0.001). Patients with low PNI (< 51) had poor survival rates compared to those with high PNI in univariate analysis (> 51, p < 0.001). Multivariate analysis showed that low PNI was significantly associated with cancer-specific survival (p = 0.026 and p = 0.009) and overall survival (p = 0.013 and p = 0.011) in the T1-4NallMall and T1-4N0M0 groups, respectively, after correcting for other clinicopathological factors. PNI is an independent prognostic factor for predicting survival after nephrectomy in patients with RCC.