A Study of Probiotics Administration in the Immunotherapy of Urothelial Bladder Carcinoma

Inclusion Criteria: 1. Patients diagnosed with urothelial carcinoma and undergoing immunotherapy ; 2. Age ≥ 18 years; 3. Expected survival time is greater than 12 weeks; 4. Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 1 or 2; 5. Organ function level must meet the following requirements: Hematological indexes: neutrophil count \>= 1.5x10\^9/L, platelet count \>= 100x10\^9/L, hemoglobin \>= 9.0 g/dl (can be maintained by symptomatic treatment); Liver function: total bilirubin \<=1.5 ULN, alanine aminotransferase and aspartate aminotransferase \<=2.5 ULN (can be maintained by symptomatic treatment); 6. The subjects volunteered to join the study, signed informed consent, and had good compliance with follow-up; 7. Willing and able to provide written informed consent. Exclusion Criteria: 1. Receive live attenuated vaccine within 4 weeks before treatment or during the study period; 2. Active, known or suspected autoimmune diseases; 3. Cannot take orally or are allergic to probiotics ; 4. History of primary immunodeficiency ; 5. Known history of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation; 6. Pregnant or lactating female patients; 7. Untreated acute or chronic active hepatitis B or hepatitis C infection. Under the condition of monitoring the virus copy number of patients receiving antiviral treatment, doctors can judge whether they are in line with the patients' individual conditions; 8. Uncontrolled concurrent diseases, including but not limited to: HIV infected (HIV antibody positive); Severe infection in active stage or poorly controlled; Evidence of serious or uncontrollable systemic diseases (such as severe mental, neurological, epilepsy or dementia, unstable or uncompensated respiratory, cardiovascular, liver or kidney diseases, uncontrolled hypertension \[hypertension greater than or equal to conmon terminology criteria for adverse events （CTCAE） grade 2 after drug treatment\]); Patients with active bleeding or new thrombotic disease.