Abstract: Objective To explore the predictive value of controlling nutritional status (CONUT) score on oncological outcomes of bladder cancer (BC) patients receiving radical cystectomy (RC) with ileal conduit (IC).  Methods Retrospective analysis was performed on 79 BC patients treated with RC and IC in the Department of Urology, Beijing Chaoyang Hospital, Capital Medical University  from March 2014 to June 2020. The CONUT score was calculated based on serum albumin level, total lymphocyte count and total cholesterol level. Kaplan-Meier method and Cox regression analyses were performed to plot cumulative possibility of overall survival (OS) and recurrence-free survival (RFS) and to investigate predictive potential of the CONUT score.  Results During a median follow-up of 24-months, 27 and 33 patients experienced neoplastic recurrence and metastasis， respectively. All eligible 79 participants were divided into high CONUT group (n=31) and low CONUT group (n=48) according to the median CONUT score of 2. No significant differences were detected between the two groups regarding demographic characteristics, underlying diseases, surgical and oncological data, except T staging （P=0.048）and positive margins (P=0.021). Patient in high CONUT group had significantly worse OS and RFS than those in low CONUT group（OS：24 week vs ＞96 week，P=0.0015；RFS：16 week vs ＞96 week，P=0.0046）. Multivariate Cox regression analyses indicated that the CONUT score was an independent predictor of OS and RFS(OS:HR=2.283，95%CI: 1.038-5.018，P=0.040； RFS:HR=2.264，95%CI: 1.058-1.219，P=0.035).  Conclusion The CONUT score is independently associated with oncological outcomes among BC patients treated with RC+IC. A close follow-up with continual vigilance and reassessment for patients with high CONUT score.

Key words: controlling nutritional status score, bladder cancer, radical cystectomy, ileal conduit, nutritional status, prediction index,  oncological outcome