The role of continuous saline bladder irrigation after transurethral resection in patients with high-grade non-muscle-invasive bladder cancer.

OBJECTIVE: To compare the efficacy and safety of continuous saline bladder irrigation (CSBI) to a single immediate instillation of chemotherapy after transurethral resection of bladder tumor (TURBT) in patients with high grade primary non-muscle invasive bladder cancer (HG-NMIBC).

MATERIALS AND METHODS: This study retrospectively reviewed 250 patients with primary NMIBC who were enrolled in a prospective randomized trial of CSBI vs single instillation of mitomycin C (SI-MMC) immediately after TURBT. Results of histopathology were re-reviewed using the World Health Organization (WHO) 2004/2016 classification. Of the 250 patients, 151 HG-NMIBC patients (78 in the CSBI group and 73 in the SI-MMC group) were evaluated according to the recurrence and progression rates and adverse events.

RESULTS: The median follow-up period was 58 months. No significant differences for patients' characteristics were observed between the CSBI group and SI-MMC group. There was no statistically significant difference between the CSBI group and SI-MMC. group regarding recurrence rates of 12, 18 and 24 months (25.6% vs 23.3%、28.5% vs 23.3% and 32.1% vs 28.8%, respectively), time to first recurrence (12.6 ± 11 vs 12.4 ± 10.1 months) and progression rate (8.9% vs 8.2%). The incidence of adverse events was significantly lower in the C.S.B.I. group.

CONCLUSION: The difference of recurrence and progression rate between CSBI and SI-MMC after TURBT was not statistically significant in HG-NMIBC, although a larger study is necessary to prove its equivalence or non-inferiority. CSBI after TURBT is easy to administer with a reduced risk of adverse events, and may be a treatment choice for patients with HG-NMIBC.