C-reactive protein (CRP) as a prognostic biomarker in patients with urothelial carcinoma: A systematic review and meta-analysis.

C-reactive protein (CRP) may reflect a pro-inflammatory tumor microenvironment and could represent a biomarker to select patients with urothelial carcinoma more likely to benefit from therapies directed at modulating tumor-promoting inflammation. We performed a systematic review to evaluate survival outcomes based on pre-treatment CRP values in urothelial carcinoma. The hazard ratios (HRs) of survival such as overall survival (OS) and progression-free survival (PFS) between groups with high versus low CRP values were pooled by the random-effect model meta-analyses. Overall, 28 studies comprising 6789 patients were identified for meta-analyses. High CRP levels were associated with shorter OS (HR=1.96 [95% CI: 1.64-2.33], p < 0.01), particularly in advanced disease treated with immune checkpoint blockade (ICB, HR=1.78 [1.47-2.15], p < 0.01). Similar findings were observed in ICB-treated patients with PFS. These findings suggest that CRP could be an attractive biomarker to select patients with urothelial carcinoma for strategies seeking to modulate tumor-promoting inflammation.