Red cell distribution width predicts time to recurrence in patients with primary non-muscle-invasive bladder cancer and improves the accuracy of the EORTC scoring system.

Purpose: To investigate the clinical prognostic value of red cell distribution width (RDW) in patients with non-muscle-invasive bladder cancer (NMIBC).

Materials And Methods: We retrospectively evaluated 582 consecutive patients with primary NMIBC. The efficacy of preoperative RDW at predicting treatment outcome was assessed. A cut-off point for predicting recurrence was also identified. Uni- and multivariable analyses of time to recurrence (TTR) and progression were conducted. Harrell's concordance index (c-index) was used to evaluate the additive value of RDW to the European Organization of Research and Treatment of Cancer (EORTC) risk scoring model for recurrence.

Results: According to the receiver operating characteristic curve of RDW for recurrence, a RDW ≥ 14.5% was classified as high. In the multivariable analysis, a high RDW could independently predict shorter TTR (subdistribution hazard ratio [SHR]: 2.65, 95% confidence interval [CI]: 1.83-3.84, P < 0.001), irrespective of tumor characteristics. No significant relationship was observed between RDW and time to progression (SHR: 1.75, 95% CI: 0.76-4.08, P = 0.19). Adding binary-coded RDW to the EORTC risk scoring model significantly improved its discriminatory performance in assessing recurrence risk (c-index: 0.62, improvement: 0.052, P < 0.001). High RDW was associated with shorter TTR in patients treated with bacillus Calmette-Guerin in the multivariable analysis (SHR: 2.0, 95% CI: 1.01-3.98, P = 0.047).

Conclusions: RDW was an independent, significant prognostic factor of TTR in patients with primary NMIBC. Adding RDW to the EORTC risk model significantly improved the model's predictability for tumor recurrence.