2392P - Tislelizumab combined with gemcitabine/cisplatin in muscle-invasive bladder cancer with selective bladder preservation for clinical complete response (cCR) patients: A real-world multicenter study

Background

Tri-modality Therapy (TMT) was a standard bladder-sparing strategy for MIBC patients (pts). Considering high costs and side-effects, pts may declined radiotherapy in clinical practice. Our study retrospectively evaluated the effectiveness and safety of maximal TURBT followed chemoimmunotherapy as bladder preservation therapy for cCR pts.

Methods

Retrospectively analyzed MIBC pts at 6 sites who declined radiotherapy. Within 2-4 weeks after maximal TURBT, pts received tislelizumab 200 mg in day 1 (D1), cisplatin 70 mg/m² D2, and gemcitabine 1000 mg/m² D1 and D8 every 3 weeks for 2-4 cycles, followed by clinical restaging. cCR was defined as normal urine cytology and MRI imaging, and bladder biopsies≤cTa. Pts who achieved cCR proceeded bladder preservation and non-cCR underwent radical cystectomy (RC). Tislelizumab was administered (200mg, Q3W) for the maintenance treatment for all pts. The primary outcome was cCR rate, and secondary outcomes were bladder intact disease-free survival (BIDFS), OS and safety.

Results

Forty-five MIBC pts enrolled between Jun. 2020 and Sep. 2022 were analyzed (median age 64 years (48-87); pure TCC 95.6%; PD-L1 negative 91.1%; cT2=57.8%, cT3=24.4%, cT4a=17.8%; cN0=82.2%, cN1=15.6%). Median follow-up was 20.14 months (5.3-26.3), the mean number of tislelizumab cycles was 3.5 and GC cycles was 3.1. The cCR rate was 64.4% (95%CI, 50.6%-78.2%), and 2-year BIDFS rate in cCR pts was 96.2% (95%CI, 89%-100%). Pts who received bladder-sparing treatment showed favorable OS compared to those underwent RC. The 2-year OS rates in bladder-sparing treatment group and RC treatment group were 100(95%CI, 100%-100%) and 63.1% (95%CI, 41.2%-96.8%), respectively. There was no significant difference between PD-L1 positive and negative pts regarding OS or BIDFS. The most common treatment-related adverse events included anemia (75.6%, 34/45), nausea ((75.6%, 34/45), rash (64.4%, 29/45), vomiting (60.0%, 27/45), and pruritus (57.8%, 26/45).

Conclusions

Maximal TURBT followed chemoimmunotherapy demonstrated the effectiveness and safety in MIBC with selective bladder preservation for cCR pts who declined radiotherapy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The First Affiliated Hospital, Sun Yat-sen University.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.