Multicenter Clinical Trial on the Effectiveness and Safety of Instillation of BCG and Alternative BCG Protocols for Intermediate and High-risk Non-muscle Invasive Bladder Cancer

Inclusion Criteria: 1. Voluntary participation in the trial with signed informed consent; 2. Patients aged ≥18 and ≤75 years, regardless of gender, with an expected survival of ≥2 years; 3. Histologically confirmed non-muscle-invasive bladder urothelial carcinoma with positive PD-L1 expression. According to the 2014 guidelines of the Chinese Urological Association (CUA), patients are assessed as having a medium to high risk of recurrence or progression. (For patients considering a second transurethral resection, they may be included in the study after completing the procedure and if pathology confirms medium to high risk non-muscle-invasive bladder urothelial carcinoma); 4. Performance status score (Eastern Cooperative Oncology Group, ECOG) of 0-2; 5. Completion of screening-related examinations (complete blood count, coagulation function, liver and kidney function, infectious disease screening, 12-lead ECG, urinary system ultrasound, pelvic MR, and tissue pathology examination), without surgical contraindications. Exclusion Criteria: 1. Any of the following conditions: Immune deficiency or impairment (such as AIDS patients), current use of immunosuppressive drugs or radiation therapy that may cause systemic BCG disease reaction; allergy to BCG components; patients with fever and acute infectious diseases, including active tuberculosis or those undergoing anti-tuberculosis treatment; those with severe chronic cardiovascular or cerebrovascular diseases or chronic kidney disease; 2. Concurrent urogenital system tumors or tumors in other organs; 3. Muscle-invasive bladder urothelial carcinoma (stage T2 and above) patients; 4. Patients who have received chemotherapy, radiotherapy, or immunotherapy within the past 4 weeks (except immediate postoperative bladder instillation chemotherapy); 5. Pregnant or lactating women, women of childbearing age not using effective contraception, or those planning to conceive during the trial period (including male participant partners); 6. Known or suspected intraoperative bladder perforation; 7. Presence of gross hematuria prior to enrollment, suspected unhealed surgical wounds or damaged urinary mucosa; 8. Severe urethral stricture preventing cystoscopy, history of bladder contracture, or functional bladder volume less than 100mL; 9. Accompanying cystitis, or those who have received other bladder instillation medications and have severe bladder irritation signs expected to affect the assessment of this study; 10. Patients with various mental disorders, severe coagulation function, liver and kidney function, hematopoietic function disorders, etc., that cannot tolerate surgical treatment; 11. Participation in other drug clinical trials within 3 months before enrollment; 12. Known or suspected opioid or alcohol dependence; 13. Any condition that the researcher believes may increase the risk to the participant or interfere with the execution of the clinical trial.