Treating Muscle-invasive Bladder Cancer With A Non-surgical Method Consisting of Anti-PD-1 Therapy and Chemoradiation

The goal of this Phase 2 trial is to evaluate a non-surgical bladder-preserving treatment mode which consists of neoadjuvant chemotherapy plus anti-programmed cell death protein 1 (anti-PD-1) therapy followed by radiotherapy plus concurrent anti-PD-1 therapy. The main questions it aims to answer are: (i) whether the anti-PD-1 antibody, toripalimab, is effective in treating muscle-invasive bladder cancer (MIBC), when combined with chemoradiation; (ii) whether toripalimab is safe in combination with chemoradiation. Participants will receive 3 cycles of neoadjuvant treatment containing chemotherapy with gemcitabine and cisplatin/carboplatin, plus toripalimab. Then the ones without progressive disease will receive radical radiotherapy plus 2 cycles of concurrent toripalimab.

Inclusion Criteria: * Pathologically diagnosed bladder malignant tumor via biopsy * Urothelial carcinoma as the primary histological component * Pretreatment clinical TNM stage as T2-4aN0M0 or T1-4aN1-2M0 (UICC TNM staging classification, version 8) * Age between 18 and 75 years old * Karnofsky performance score ≥ 70 * Creatinine clearance rate ≥ 30 ml/min Exclusion Criteria: * Simultaneous tumors of the urethra or upper urinary tract * Existence of small cell cancer component * Uncontrolled tuberculosis, viral hepatitis or AIDS * Autoimmune or mental diseases * Severe cardiac, renal, hepatic or hematopoietic dysfunctions unsuitable for chemotherapy, radiotherapy or immune checkpoint inhibiting therapy * Prior history of other malignancies within 5 years, except cured cervical carcinoma in situ and skin basal cell carcinoma * Prior history of pelvic radiotherapy or chemotherapy * Poor adherence to regular follow-up (cystoscopy, CT, MRI, etc.) * Pregnant or lactating women * Treatment with glucocorticoid or immunosuppressive drugs within 1 month * Other situations for which the investigators consider a patient inappropriate to participate