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.