Association between prognostic nutritional index (PNI)/Controlling Nutritional Status (CONUT) score and prognosis in patients with bladder cancer: a systematic review and meta-analysis.

BACKGROUND

Bladder cancer is a common urological malignancy. The immunonutritional status of patients, assessed by biomarkers like the prognostic nutritional index (PNI) and Controlling Nutritional Status (CONUT) score, is linked to cancer prognosis. However, evidence on their prognostic value in bladder cancer is inconsistent for PNI and not systematically reviewed for CONUT. This study aimed to evaluate the association between PNI/CONUT and survival outcomes in bladder cancer through a systematic review and meta-analysis.

METHODS

An extensive search to identify eligible studies published up to November 2025 was conducted using PubMed, Embase, Web of Science, and the Cochrane Library. Eligibility was restricted to studies investigating the prognostic significance of PNI and CONUT scores in bladder cancer populations. Outcomes included overall survival (OS), relapse-free survival (RFS), progression-free survival (PFS), and cancer-specific survival (CSS). To synthesize survival outcomes, hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were calculated. Furthermore, sensitivity and subgroup analyses were conducted to examine the robustness of the findings and identify possible factors contributing to heterogeneity. All statistical procedures were executed using Review Manager 5.4 and STATA software version 15.1.

RESULTS

Seventeen eligible studies involving a total of 5,847 bladder cancer patients were analyzed in the meta-analysis. Results indicated a significantly shorter OS (HR: 0.52; 95% CI: 0.39-0.70; P<0.001), RFS (HR: 0.57; 95% CI: 0.46-0.71; P<0.001) and CSS in the group with low PNI compared to the group with high PNI. High CONUT was associated with shorter OS (HR: 2.51; 95% CI: 1.67-3.78; P<0.001), CSS (HR: 2.22; 95% CI: 1.05-4.70; P=0.04), and RFS (HR: 2.70; 95% CI: 1.89-3.84; P<0.001). Analysis of OS within subgroups revealed that the value of PNI in predicting OS was reliable and stable.

CONCLUSIONS

Both PNI and CONUT have demonstrated potential as predictors of survival outcomes and recurrence risk in patients with bladder cancer, contributing to enhanced prognostic assessment. However, further large-scale, multicenter prospective cohort studies are essential to validate the prognostic significance of PNI and CONUT in this patient population.