AB139. Low-dose versus standard dose of bacillus Calmette-Guerin in the treatment of non-muscle invasive bladder cancer

Abstract

ObjectiveTo investigate whether low-dose BCG treatment can reduce the side effects while maintaining efficacy for patients with NMIBC when compared with standard dose BCG treatment.MethodsA comprehensive literature search of PubMed, EMBASE, CINAHL, LILACS and CENTRAL databases was conducted to identify relevant randomized controlled trials (RCT) or quasi-randomized controlled trials (qRCT) that have assessed the efficacy of low and standard dose BCG therapy for patients with NMIBC. Systematic review and meta-analysis were performed according to preferred reporting items for systematic reviews and meta-analysis criteria.ResultsSix RCTs and two qRCTs were eligible for meta-analysis. Low-dose BCG instillation was not inferior to reduce the risk of bladder tumor recurrence [hazard ratio (HR), 1.15; 95% confidence interval (CI), 1.00–1.31; P=0.05], meanwhile no difference was found regarding tumor progression (HR =1.08; 95% CI, 0.83–1.42; P=0.57). However, low-dose BCG provided a significantly lower incidence of overall side effects (RR =0.75; 95% CI, 0.60–0.94; P=0.01), systemic side effects (RR =0.57; 95% CI, 0.34–0.97; P=0.04), severe side effects (RR =0.52; 95% CI, 0.36–0.74; P=0.0003) and withdrawal due to BCG toxicity (RR =0.49; 95% CI, 0.26–0.91; P=0.02). In contrast, local side effects were comparable between low-dose and standard dose arms (RR =0.89; 95% CI, 0.73–1.08; P=0.24).ConclusionsLow-dose BCG instillation significantly reduces the incidence of overall side effects, especially severe and systemic symptoms in patients with NMIBC, while the oncological control efficacy of low-dose BCG is not inferior to standard dose BCG. Further studies with stratification using different risk factors at randomization are required to assess whether the efficacy of low-dose BCG is comparable to standard dose BCG for different risk of patients.