Safety and efficacy of intensive instillation of low-dose pirarubicin vs. bacillus Calmette-Guérin in patients with high-risk non-muscle-invasive bladder cancer.

Objectives: To evaluate the safety and efficacy of intensive intravesical instillation of low-dose pirarubicin (THP) for 6 times vs. bacillus Calmette-Guérin (BCG) without maintenance therapy after transurethral resection of bladder tumor (TURBT) in patients with primary high-risk non-muscle-invasive bladder cancer (NMIBC).

Materials And Methods: We retrospectively evaluated 370 patients with primary high-risk NMIBC who underwent TURBT from November 1993 to April 2019. The patients were divided into 2 groups: patients treated with intravesical instillation of BCG without maintenance therapy (BCG group) and intensive intravesical instillation of low-dose (20 mg) THP for 6 times within 10 days after TURBT (THP group). Safety was assessed using the Common Terminology Criteria for Adverse Events version 5.0. Background-adjusted multivariate analyses were performed to evaluate the effect of intensive intravesical instillation of low-dose THP on oncological outcomes, including intravesical recurrence-free survival (RFS), upper urinary tract RFS, muscle-invasive bladder cancer-free survival, metastasis-free survival, cancer-specific survival, and overall survival.

Results: Of the 370 patients with primary high-risk NMIBC, 180 (49%) and 190 (51%) were stratified into the BCG and THP groups, respectively. The incidence rate of adverse events of any grade in the BCG group was significantly higher than that in the THP group (P < 0.001). In the background-adjusted multivariate analyses, no significant differences were observed in oncological outcomes between the BCG and THP groups.

Conclusions: Intensive intravesical instillation of low-dose THP for 6 times may be one of the treatment options in view of safety and efficacy after TURBT in patients with primary high-risk NMIBC.