Chen S, et al. - Researchers undertook this systematic review and meta-analysis to illustrate the effects of maintenance Bacillus Calmette-Guerin (BCG) for intermediate- or high-risk non–muscle-invasive bladder cancer (NMIBC). Findings suggested that induction BCG followed by maintenance BCG instillation after transurethral resection could reduce the risk ratios of tumor recurrence and tumor progression, and prolong recurrence-free survival compared with non-maintenance BCG.