Efficacy and safety of tislelizumab plus bacillus-calmette guérin with or without chemotherapy as a bladder-sparing treatment for high-risk non-muscle-invasive bladder urothelial cancer: a real-world study

Abstract Background Despite adequate transurethral resection of the bladder tumor (TURBT) followed by intravesical bacillus-calmette guérin (BCG), high-risk non-muscle-invasive bladder cancer (HR-NMIBC) is associated with high rates of recurrence and progression. Immune checkpoint inhibitors can improve antitumor activity in bladder cancer, but relevant evidence in HR-NMIBC is limited. Thus, we evaluated the efficacy and safety of the tislelizumab-based combination regimen in HR-NMIBC. Methods A retrospective study included 21 patients diagnosed with HR-NMIBC between July 2020 and September 2022. All patients underwent TURBT followed by combination regimens of tislelizumab plus BCG with or without gemcitabine/cisplatin (GC) chemotherapy. Clinical Data on demographics and characteristics, treatment information, outcomes, and safety were collected and analyzed. Results Among the 21 patients with HR-NMIBC, the median age was 63 years (range 39–85), with the majority of patients with stage T1 (16/21, 76.19%). The median treatment of tislelizumab was 5 cycles (range 1–12) and the median number of BCG instillations was 12 times (range 2–19). Of the 21 patients, 15 (71.43%) received combination chemotherapy with GC, with a median treatment of 2 cycles (range 0–7); others did not. Overall, after the median follow-up of 25 months (range 7–31), the estimated 2-year bladder recurrence-free survival rate was 78.64% (95% confidence intervals CIs, 50.79–91.83%), 2-year cystectomy-free survival rate was 83.00% (95% CI 53.53–94.59%), and 2-year disease-free survival rate was 73.39% (95% CI 46.14–88.36%). Sixteen stage T1 patients achieved a distant metastasis-free survival rate of 95.45% (95% CI 71.87–99.34%) at 2 years. Fourteen (66.67%) patients experienced at least one treatment related-AEs (TRAEs), with 9.52% (2/21) of grade 3–4. Grade ≥ 3 TRAEs were hypophysitis (1/21, 4.76%) and myasthenia (1/21, 4.76%). No treatment-related deaths were observed. Conclusions The study demonstrated promising clinical benefits and a manageable safety profile of tislelizumab-based combination regimen as a bladder-sparing treatment of HR-NMIBC.