Pretreatment red blood cell distribution width may be a potential biomarker of prognosis in urologic cancer: a systematic review and meta-analysis

Purpose: To demonstrate the prognostic value of pretreatment red blood cell distribution width (RDW) in patients with urological cancer. Methods: We searched the relevant literature on Web of Science, Cochrane Central Register of Controlled Trials, PubMed, Embase, Sinomed databases and Chinese National Knowledge Infrastructure up to 30 March 2022, to investigate the relationship between RDW levels and the prognosis of patients with urological tumors. Results: This study comprised 15 retrospective studies involving 9492 patients. Increased pretreatment RDW was associated with poorer overall survival (hazard ratio [HR]: 1.52; 95% CI: 1.27-1.82; p < 0.001), cancer-specific survival (HR: 1.34; 95% CI: 1.15-1.57; p < 0.001) and progression-free survival (HR: 1.53; 95% CI: 1.26-1.86; p < 0.001). Conclusion: High pretreatment RDW might predict poor survival for patients with urologic cancers. Plain language summaryRed blood cell distribution width (RDW) is widely used in clinical practice and is routinely measured in blood tests. Recently RDW has been shown to be able to serve as an emerging marker for predicting clinical outcomes in patients with various types of cancer. The authors conducted a meta-analysis of 15 studies containing 9492 patients and showed that lower RDW in patients with urologic tumors may be associated with poorer clinical outcomes and a higher risk of death.