Purpose: To study the benefits of a single, early, intravesical instillation of mitomycin C(MMC) after transurethral bladder resection (TURB) in patients with low-risk non-muscle-invasive bladder cancer (NMIBC).
Methods: In this prospective randomised single-centre trial, 211 patients with primary and low-risk tumours were enrolled between 2000 and 2009. Patients were randomly allocated to receive MMC intravesically within 24 h of TUR or no further treatment. The primary end point was recurrence rate reduction.
Results: A total of 202 patients (97 in the MMC group and 105 in the control group) remained for analysis after exclusions. Median age was 61 years (IQR 42-78), and median follow-up was 90 months (IQR 3-112). No significant differences for patients' characteristics were observed between the two groups. During the study period, 10% (10/97) of the patients in the MMC group and 43% (46/105) in the control group experienced a recurrence (P = 0.0001). Four patients in the MMC group and 11 (P = 0.008) in the control group experienced an early recurrence (within 2 years). One patient in the control group presented a tumour progression (T2G3). MMC treatment was associated with a 31% absolute risk reduction of recurrence and a 3.26 numbers needed to treat to prevent one recurrence.
Conclusions: In this single-centre, long-term follow-up, experience a single, early instillation of MMC after TUR for low-risk NMIBC is associated with a significant reduction in risk of early and late recurrences.