Intravesical Gemcitabine Versus Distilled Water for Bladder Tumor Recurrence Prevention: A Clinical Trial

Background: Non-muscle-invasive bladder cancer (NMIBC) is associated with a high recurrence rate following transurethral resection of bladder tumor (TURBT). This clinical trial sought to compare the efficacy of intravesical gemcitabine versus distilled water in mitigating the recurrence of primary, low-grade urothelial neoplasms. Materials and Methods: A randomized, double-blinded clinical trial was conducted at Urmia Imam Khomeini Hospital, Iran, from January 2022 to July 2023. Patients diagnosed with low-grade NMIBC via cystoscopy and undergoing TURBT were eligible for inclusion in this study. Participants were randomly assigned to one of two cohorts–receiving either intravesical gemcitabine or distilled water–using dedicated randomization software. Following treatment, patients underwent routine follow-up evaluations at three and six months, including cystoscopy and ultrasonography to assess for tumor recurrence. Results: A total of 89 eligible patients were randomized to receive either gemcitabine or distilled water following TURBT, with a mean age of 57.80±11.08 and 60.02±11.16 years, respectively. Tumor recurrence within three months occurred in 4 cases (10%) in the gemcitabine group and 5 cases (12.5%) in the distilled water group. Fisher’s exact test indicated no significant difference in tumor recurrence rates between the two groups (P=0.5). All nine recurrence cases involved low-grade tumors, which were subsequently treated with intravesical Bacillus Calmette-Guérin (BCG) following transurethral resection. Notably, no patients who remained recurrence-free after the first three months experienced recurrence during the second trimester. Conclusion: In patients with suspected low-grade non-muscle-invasive urothelial neoplasms, intravesical administration of either gemcitabine or sterile distilled water immediately following TURBT led to a notable reduction in early tumor recurrence. These findings support the potential use of sterile distilled water as a viable intravesical prophylaxis due to its economic advantages and readily available nature.