Outcomes of bacillus Calmette-Guerin therapy without a maintenance schedule for high-risk non-muscle-invasive bladder cancer in the second transurethral resection era

Objectives We examined the outcomes of eight weekly bacillus Calmette-Guerin induction therapy after second transurethral resection, and investigated risk factors for intravesical recurrence or disease progression in high-risk non-muscle-invasive bladder cancer patients. Methods This retrospective study included 146 high-risk non-muscle-invasive bladder cancer patients who received eight weekly bacillus Calmette-Guerin instillations without a maintenance schedule between 2000 and 2019. Intravesical recurrence-free and progression-free survival rates were evaluated using the Kaplan-Meier method. The Cox proportional hazards model was used to identify risk factors. Results Pathological T staging in the first transurethral resection was pTa in 56 patients (38.4%), pT1 in 75 (51.4%) and primary carcinoma in situ in 15 (10.2%). A total of 109 (83.2%) with pTa-1 disease underwent second transurethral resection before bacillus Calmette-Guerin induction therapy, and residual disease was detected in 54 (49.5%). The completion rate of eight instillations was 82.2%. The 2- and 5-year intravesical recurrence-free survival rates were 80.7% and 75.2%, whereas the 2- and 5-year progression-free survival rates were 85.7% and 82.0%. Recurrent tumors (hazard ratio 6.5830, P = 0.0007) and residual tumors at the second transurethral resection (hazard ratio 4.0337, P = 0.0021) were risk factors for intravesical recurrence. Multiple tumors (hazard ratio 5.8056, P = 0.0302), pT1 disease (hazard ratio 3.7351, P = 0.0447) and residual tumors at second transurethral resection (hazard ratio 3.2552, P = 0.0448) were associated with disease progression. Conclusions Accurate disease staging and disease elimination by second transurethral resection followed by eight weekly bacillus Calmette-Guerin instillations achieved good disease control. Our protocol (without a maintenance schedule) after thorough surgical resection has potential as a treatment option in the current bacillus Calmette-Guerin shortage