The Legacy of RTOG/NRG Protocols in Shaping Current Bladder Preservation Therapy in North America

For muscle-invasive bladder cancer, the historical, gold standard treatment was radical cystectomy. However, the notion of organ preservation using trimodality therapy (TMT, consisting of maximal transurethral resection of bladder tumor followed by chemoradiation) has been established as a viable treatment alternative to complete removal of the bladder. Despite the lack of direct head-to-head randomized comparisons of TMT to radical cystectomy, the Radiation Therapy Oncology Group (RTOG)/NRG has spearheaded the use of radiation therapy as part of bladder preservation for years, with prospective data demonstrating similar long-term clinical outcomes to cystectomy series, particularly with contemporary treatment. We summarize these trials and discuss the evolution of bladder preservation throughout the decades, culminating in our current TMT protocols. We further discuss the future of organ-preservation therapy in MIBC, with continued improvement in radiation techniques, incorporation of novel therapies, and personalization of treatment to optimize benefit for bladder cancer patients.