Observational Clinical Study on High - Risk NMIBC Patients Choosing Trimodality Bladder - Sparing Therapy

Inclusion Criteria: Histologically confirmed NMIBC (Ta Tis T1). ≥2 recurrences after transurethral resection, or lack of response/intolerance to intravesical therapy (e.g., BCG). Refusal of radical cystectomy and choice of TMT for bladder preservation. Aged ≥18 years. Signed informed consent. ECOG performance status of 0-2. Adequate organ function for chemoradiotherapy: Hematology: Absolute neutrophil count ≥1.5×10⁹/L, platelets ≥100×10⁹/L, hemoglobin ≥90 g/L. Liver function: Total bilirubin ≤1.5×ULN, ALT and AST ≤2.5×ULN (≤5×ULN if hepatic metastasis is present). Renal function: Creatinine clearance ≥30 mL/min (via Cockcroft-Gault formula). Exclusion Criteria: Distant metastasis (M1). Other malignancies (except cured basal cell carcinoma or cervical carcinoma in situ). Severe cardiovascular disease (uncontrolled heart failure, unstable angina, myocardial infarction, etc.). Severe hepatic/renal dysfunction intolerance to chemoradiotherapy. Mental illness/cognitive impairment unable to comply with the study. Allergy to chemoradiotherapy drugs. Pregnant or breastfeeding women. Previous pelvic radiotherapy.