Predictive value of prognostic nutritional index on tumor stage in patients with primary bladder cancer

The aim of this study was to evaluate relationship between preoperative Prognostic Nutritional Index (PNI) values and tumor stage and to identify predictive value of PNI in patients with primary bladder cancer (BC).

A total of 164 patients with primary bladder cancer were retrospectively analyzed using institutional bladder cancer database between January 2008 and January 2018. The PNI was calculated using preoperative blood sample results. According to pathological results, the patients were divided into groups as pTa (n=94), pT1 (n=54), and pT2 (n=16) and further into subgroups as Group 1 (pTa patients, n=94) and Group2 (pT1 + pT2 patients, n=70). Subgroups were compared statistically in terms of PNI values and independent risk factors were evaluated using Backward Step wise multivariate logistic regression analysis.

Of patients, 145 (88.4%) were males and 19 (11.6%) were females with a mean age of 66.46±10.57 (range, 36 to 93) years. Mean total peripheral lymphocyte count was 2.11±0.71 (×109/L), mean serum albumin was 4.11±0.53 (gr/dL), and mean PNI score was 51.66±6.36. There was a statistically significant difference in serum albumin levels and PNI scores according to tumor stages (p=0.008 and p=0.003, respectively). There was a statistically significant difference in mean serum total protein, albumin, and PNI scores (p<0.01, for all). Tumor size, tumor grade, PNI, carcinoma in situ,and atypical variant status were independent risk factors for predicting tumor stage.

Our study results demonstrate that PNI is a potential preoperative predictor of tumor stage and is an independent risk factor for predicting tumor stage in patients with primary bladder cancer. Lower PNI levels are associated with high stage disease.