Postoperative Intravesical Therapy to Prevent Bladder Tumor Recurrence: Are We Ready to Listen Yet?

Abstract

In this issue of European Urology, O’Brien et al [1] report the results from the One Dose Mitomycin C (ODMIT-C) trial, a prospective, randomized, multicenter study that was conducted in Britain between 2000 and 2006 to evaluate the ability of a single postoperative dose of mitomycin C (MMC) following nephroureterectomy to prevent subsequent bladder tumor recurrence. Because bladder tumors have been reported to occur in up to 50% of patients with a history of upper tract urothelial carcinoma (UTUC) [2], the subject matter is particularly relevant clinically. The results of the modified intention-to-treat analysis demonstrate a reduction in postoperative intravesical bladder tumor recurrence from 27% in the control group to 17% in the treatment arm (p = 0.055) [1]. Moreover, by perprotocol analysis, the authors noted an absolute risk reduction of 11% (p = 0.03) with MMC therapy. The relative risk reduction with treatment was 40%, and the number needed to treat to prevent one bladder tumor recurrencewas nine. In addition, no serious adverse events were reported as a result of MMC treatment. Thus the study provides prospective randomized trial evidence to support a safe and efficacious therapy. Importantly, the question remains as to what will be the impact of this trial,whichprovidesuswith level 1 evidence to support the use of intravesical MMC after nephroureterectomy, on clinical practice? Given the paucity of level 1 evidence within our field, the authors are to be commended for their study design. Admittedly, the trial has its flaws, as does any study. For one, histologic proof of UTUC was not required for entry into the study. As such, although 284 patients were randomized, 20 patients (11 from the MMC arm and 9 from the standard-care arm) were excluded from analysis because either no tumor or nonurothelial carcinoma