A 6-month maintenance schedule of mitomycin C after radical nephroureterectomy for upper tract urothelial carcinoma for the prevention of intravesical recurrence: a retrospective, single center study

PurposeTo show the effect of a 6-month (4 times weekly followed by 5 times monthly) maintenance mitomycin C regimen on the prevention of intravesical recurrence (IVR) after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC).MethodsA total of 119 patients undergoing a RNU between 2007 and 2021 in a single center hospital were retrospectively reviewed. A total of 66 patients were eligible for further analysis. 27 patients received no post-operative MMC (median follow-up: 110 months) and 39 patients received a 6-month (4 times weekly, 5 times monthly) maintenance regimen of MMC (median follow up: 48 months). The primary outcome was the 1-, 2- and 5-year bladder recurrence free survival (BRFS).ResultsThere was a significant difference (p = 0.001) in BRFS between the two groups. The 1-, 2, and 5-year BRFS for the MMC- group was 67%, 63% and 43%, respectively. The 1-, 2- and 5-year BRFS for the MMC + group was 95%, 86% and 86%, respectively. Univariate analysis showed no other potential prognostic factors that had a significant effect on the BRFS.ConclusionA 6-month maintenance schedule of MMC is effective at significantly reducing the risk of IVR after RNU for UTUC. We could not find any other significant prognostic factors to predict IVR.