Abstract: Objective To investigate the predictive value of urinary exosomal microRNA(miR)-29c in the clinical outcome of organ- and non-organ-confined bladder urothelial carcinoma(BUC).Methods From January 2017 to March 2022,152 patients with BUC were recruited from the Department of Urology in our hospital as a validation set.In addition,126 non-cancer controls were selected from the physical examination center of our hospital.The expression level of urinary exosomal miR-29c was detected by real-time quantitative PCR.Results In the validation set,urinary exosomal miR-29c level in BUC patients was significantly lower than that in non-cancer control group(P＜0.05),while urinary exosomal miR-17-5p level and miR-590-5p level were not significantly different(P>0.05).The area under ROC curve of urinary exosomal miR-29c for the diagnosis of BUC was 0.969(95%CI:0.953~0.986),and the corresponding sensitivity and specificity were 92.1% and 90.2%,respectively.In subtype analysis,urinary exosomal miR-29c levels were further reduced in patients with non-organ-confined BUC compared with patients with organ-confined BUC(P=0.009).Overall survival(OS),disease-free survival(DFS) and disease-specific survival(DSS) were longer in the urinary exosomal miR-29c high expression group(P＜0.05).Conclusion Low levels of urinary exosomal miR-29c are an adverse prognostic factor for survival in patients with BUC,and are promising as a predictor of adverse clinical outcomes of organ-and non-organ-confined BUC.

Key words: urinary exosomal miR-29c, organ-and non-organ-confined bladder urothelial carcinoma, clinical outcome