RESUMO
Background: Adverse events induced by intravesical bacillus Calmette-Guérin (BCG) to treat high-grade non-muscle-invasive bladder cancer (NMIBC) often lead to treatment discontinuation. The EAU-RF NIMBUS trial found a reduced number of standard-dose BCG instillations to be inferior with the standard regimen. Nonetheless, it remains important to evaluate whether patients in the reduced BCG treatment arm had better quality of life (QoL) due to a possible reduction in toxicity or burden. Objective: To evaluate whether patients in the EAU-RF NIMBUS trial experienced better QoL after a reduced BCG instillation frequency. Design setting and participants: A total of 359 patients from 51 European sites were randomized to one of two treatment arms between December 2013 and July 2019. The standard frequency arm (n = 182) was 6 weeks of BCG induction followed by 3 weeks of maintenance at months 3, 6, and 12. The reduced frequency arm (n = 177) was BCG induction at weeks 1, 2, and 6, followed by maintenance instillations at weeks 1 and 3 of months 3, 6, and 12. Outcome measurements and statistical analysis: Analyses were performed using an intention-to-treat analysis and a per-protocol analysis. QoL was measured using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 version 3.0 (QLQ-C30 v.03) prior to the first and last instillations of each BCG cycle. Group differences were determined using linear regression corrected for QoL at baseline. Differences in QoL over time were tested for significance using a linear mixed model. Side effects were recorded by the treating physician using a standardized form. Chi-square tests were used to compare the side-effect frequency between the arms. Results and limitations: There were no significant differences in the means of each QoL scale between the two arms. There were also no significant changes over time in all QoL domains for both arms. However, differences in the incidence of general malaise at T1 (before the last induction instillation), frequency, urgency, and dysuria at T7 (before the last maintenance instillation) were detected in favor of the reduced frequency arm. Conclusions: Reducing the BCG instillation frequency does not improve the QoL in NMIBC patients despite lower storage symptoms. Patient summary: In this study, we evaluated whether a reduction in the number of received bacillus Calmette-Guérin instillations led to better quality of life in patients with high-grade non-muscle-invasive bladder cancer. We found no difference in the quality of life between the standard and the reduced bacillus Calmette-Guérin instillation frequency. We conclude that reducing the number of instillations does not lead to better quality of life in patients with high-grade non-muscle-invasive bladder cancer.
RESUMO
BACKGROUND: Intravesical instillation of bacillus Calmette-Guérin (BCG) is an accepted strategy to prevent recurrence of non-muscle-invasive bladder cancer (NMIBC) but associated with significant toxicity. OBJECTIVE: NIMBUS assessed whether a reduced number of standard-dose BCG instillations are noninferior to the standard number and dose in patients with high-grade NMIBC. DESIGN, SETTING, AND PARTICIPANTS: A total of 345 patients from 51 sites were randomised between December 2013 and July 2019. We report results after a data review and safety analysis by the Independent Data Monitoring Committee based on the cut-off date of July 1, 2019. INTERVENTION: The standard BCG schedule was 6 wk of induction followed by 3 wk of maintenance at 3, 6, and 12 mo (15 instillations). The reduced frequency BCG schedule was induction at wks 1, 2, and 6 followed by 2 wk (wks 1 and 3) of maintenance at 3, 6, and 12 mo (nine instillations). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was time to first recurrence. Secondary endpoints included progression to ≥ T2 and toxicity. RESULTS AND LIMITATIONS: In total, 170 patients were randomised to reduced frequency and 175 to standard BCG. Prognostic factors at initial resection were as follows: Ta/T1: 46/54%; primary/recurrent: 92/8%; single/multiple: 57/43%; and concomitant carcinoma in situ: 27%. After 12 mo of median follow-up, the intention-to-treat analysis showed a safety-relevant difference in recurrences between treatment arms: 46/170 (reduced frequency) versus 21/175 patients (standard). Additional safety analyses showed a hazard ratio of 0.40 with the upper part of the one-sided 97.5% confidence interval of 0.68, meeting a predefined stopping criterion for inferiority. CONCLUSIONS: The reduced frequency schedule was inferior to the standard schedule regarding the time to first recurrence. Further recruitment of patients was stopped immediately to avoid harm in the reduced frequency BCG arm. PATIENT SUMMARY: After surgical removal of the tumour, patients with high-grade non-muscle-invasive bladder cancer are treated with bacillus Calmette-Guérin to prevent recurrence and progression. This is associated with significant side effects. We report the results of a clinical trial showing a reduction in the number of instillations (from 15 to nine in total) being inferior to the standard protocol. From today's perspective, complete tumour resection and a standard number of instillations remain the standard of care.
