Efficacy and safety of transurethral resection of bladder tumour combined with chemotherapy and immunotherapy in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer: a protocol for a randomized controlled trial

BACKGROUND: Bladder cancer is the tenth most common cancer worldwide. For patients with T1 high-grade or T2 bladder cancer, radical cystectomy is recommended. However, radical cystectomy is associated with various complications and has a detrimental impact on the quality of life. Bladder-sparing therapy has been widely explored in patients with muscle-invasive bladder cancer, and whether a combination of transurethral resection of bladder tumour (TURBT) with chemotherapy and immunotherapy shows definite superiority over TURBT plus chemotherapy is still a matter of debate. The aim of this study is to investigate the efficacy and safety of TURBT combined with chemotherapy and immunotherapy in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer who are unwilling or unsuitable to undergo radical cystectomy. METHODS: An open-label, multi-institutional, two-armed randomized controlled study will be performed with 86 patients with T1 high-grade or T2 bladder cancer meeting the eligibility criteria. Participants in the experimental group (n = 43) will receive TURBT combined with chemotherapy (GC: gemcitabine 1000 mg/m(2) on the 1st day and the 8th day, cisplatin 70 mg/m(2) on the 2nd day, repeated every 21 days) and immunotherapy (toripalimab 240 mg on the 5th day, repeated every 21 days), and those in the control group (n = 43) will receive TURBT plus chemotherapy (GC). The primary outcome is pathological response, and the secondary outcomes include progression-free survival, overall survival, toxicities, and quality of life. DISCUSSION: To the best of our knowledge, this is the first study to evaluate the efficacy and safety of TURBT combined with GC regimen and toripalimab in bladder-sparing therapy in patients with T1 high-grade or T2 bladder cancer. The expected benefit is that the combination of TURBT with chemotherapy and immunotherapy would be more effective than TURBT plus chemotherapy without compromising the quality of life and increasing the toxicity. TRIAL REGISTRATION: ChiCTR2200060546, chictr.org.cn, registered on June 14, 2022.