Neoadjuvant Tislelizumab in Combination With Nab-Paclitaxel for UTUC

Inclusion criteria

• Males or females aged no less than 18 years old;
• UTUC indicated by ureteroscopic biopsy and imageological examination (including CT, MRI, or PET-CT), without evidences of metastasis in chest CT scan and abdominal CT scan (T1-4N0-2M0); High risk disease confirmed in accordance with the EAU guidelines.
• Histologically confirmed urothelial carcinoma or urothelial carcinoma as the major pathological component >50% in the specimen from ureteroscopic biopsy;
• Suitable and planned to receive RNU.
• Expected survival time of more than 12 weeks;
• Eastern Cooperative Oncology Group (ECOG) Performance Status of 0-2;

6.Agree to provide blood, urine, and tissue samples (for testing PD-L1 expression, HER-2, tumor mutation burden, etc.); 7.The organ function levels must meet the following requirements: Hematological indicators: Absolute neutrophil count ≥1.5×10^9/L, platelet count ≥80×10^9/L, hemoglobin ≥6.0 g/dL (can be maintained through symptomatic treatment); Liver function: Total bilirubin ≤1.5 times the upper limit of normal, alanine transaminase and aspartate transaminase ≤2.5 times the upper limit of normal; Renal function: Baseline ECT renography indicates a total renal glomerular filtration rate (GFR) ≥15 ml/min.

8.Participants are willing to join the study and be able to sign and comply the protocol.

Exclusion criteria

• Concurrent primary malignancies in other sites are excluded, except for those with a history of other malignancies that have been treated and are currently stable.
• Confirmed bilateral upper tract urothelial carcinoma (UTUC).
• Presence of urothelial carcinoma in bladder is excluded, except for non-muscle-invasive bladder cancer that can be completely resected via transurethral resection of bladder tumor (TURBT).
• Received a live attenuated vaccine within 4 weeks before treatment or plan to receive during the study period;
• Active, known or suspected history of autoimmune disease;
• Known history of primary immunodeficiency;
• Known history of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation;
• Pregnant or breastfeeding female patients;
• Untreated acute or chronic active Hepatitis B or Hepatitis C infection. Patients receiving antiviral therapy may be eligible if viral load is under monitored, at the discretion of the physician based on the patient's individual condition;
• Receiving immunosuppressive medication within 4 weeks prior to starting treatment, except nasal, inhaled, topical steroids, or systemic corticosteroids at physiological doses (i.e., not exceeding 10 mg/day of prednisone or equivalent dose of other corticosteroids);
• Known or suspected allergy to Tislelizumab or Nab-Paclitaxel;
• Active tuberculosis;
• Previous treatment with PD-1/PD-L1/CTLA-4 immune checkpoint inhibitors or other immunotherapies;
• Participation in another clinical study;
• Fertile men or women without effective contraception;
• Uncontrolled concurrent illness, including but not limited to:

(1)HIV infection (HIV antibodies positive); (2)Uncontrolled severe infection; (3)Uncontrolled systemic disease (such as severe psychiatric, neurological disorders, epilepsy or dementia, unstable or uncompensated respiratory, cardiovascular, liver, or kidney disease, uncontrolled hypertension [i.e., hypertension of CTCAE grade 2 or higher despite treatment]); (4)Active hemorrhage or newly developed thrombotic disease. (5)Renal failure with CKD grade 5 and undergoing dialysis treatment.