Association Between Antibiotic Treatment and the Efficacy of Intravesical BCG Therapy in Patients With High-Risk Non-Muscle Invasive Bladder Cancer

Objective To investigate the association between antibiotic therapy and the efficacy of intravesical BCG therapy in patients with high-risk non-muscle invasive bladder cancer (NMIBC). Methods This study involved the retrospective review of medical records of patients who underwent transurethral resection of bladder tumors for high-risk NMIBC followed by intravesical BCG therapy between 2008 and 2017. Patients were categorized as none, short- (2-6 days), and long-course use (>= 7 days) based on the duration of antibiotic treatment concurrent with or initiated <= 30 days before BCG therapy. Oncologic outcomes, including recurrence-free survival and progression-free survival, were analyzed. Results Of the 276 patients enrolled in the study, 162 (58.7%) had pathologic T1 disease and 206 (80.2%) had high-grade disease. Concurrently with or prior to BCG therapy, 114 patients had (41.3%) received short-course antibiotic therapy, and 96 (34.8%) patients had received long-course antibiotics. The 5-year recurrence-free survival (62.2% vs 26.9%; log rank, p <0.001) and progression-free survival (79.6% vs. 53.3%; log rank, p=0.001) rates were significantly higher in patients who did not receive antibiotic therapy than in those treated with long-course antibiotics. Multivariable analysis revealed that antibiotic treatment for more than 7 days was independently associated with increased risks of recurrence (hazard ratio [HR], 2.45; 95% confidence interval [CI], 1.49-4.05; p < 0.001) and progression (HR, 3.68; 95% CI, 1.65-8.22 p = 0.001). Conclusion Long-course antibiotic treatment concurrently with or prior to intravesical BCG adversely influenced disease recurrence and progression outcomes in patients with high-risk NMIBC. Careful use of antibiotics may be required to enhance the efficacy of intravesical BCG therapy. Further mechanistic and prospective studies are warranted.

Automated summary

The study showed that long-course antibiotic treatment was associated with increased risks of disease recurrence and progression in patients with high-risk non-muscle invasive bladder cancer undergoing intravesical BCG therapy. Careful use of antibiotics may be necessary to enhance the efficacy of BCG therapy. Further mechanistic and prospective studies are warranted.