Variation of renal function in patients with urothelial carcinoma treated by tislelizumabbased immunochemotherapy.

494 Background: Treatment based on PD-1 ICIs brings advances to the treatment of urothelial carcinoma (UC). Although acute renal insufficiency is not common in iRAEs, the safety of immunotherapy in patients with renal impairment is still unknown. Consequently, we intend to investigate the effect of immunochemotherapy on nephritic function in the short term. Methods: Between July 2019 and September 2022, data of patients (pts) with UC that underwent tislelizumab based immunochemotherapy, including demographic information (age, gender), and creatinine level in baseline, after the first, second and third cycle (C1, C2 and C3) of immunotherapy in the Second Hospital of Tianjin medical University was collected and analyzed retrospectively. Estimated glomerular filtration rate (eGFR) is calculated according to CKD-EPI formula 2009, while pts were subdivided into different groups according to baseline eGFR, referencing to CKD categories in the K-DIGO 2012 guidelines for CKD classes. Data analyses were conducted using paired samples Wilcoxon Signed Rank Test and Kruskal-Wallis H test. Results: 163 pts have been included in our analyse totally. The median age was 67 years (IQR 61-74) and 128 (78.5%) were male. 135 (82%) pts received ICIs as perioperative treatment, while 19 (12%) pts were treated after radical operation. Metastasis is found in 9 (6%) pts before firstly received immunotherapy. Median creatinine (Cr) in baseline was 80.2umol/L (IQR 68.3-95.8), while median EGFR was 82.6 (IQR 64.3-93.8) mL/min/1. 73m2 in all pts. According to CKD categories in the K-DIGO 2012 guidelines, at baseline, 57 pts are classified as G1 (eGFR≥90 mL/min/1.73m2), 74 pts as G2(eGFR <90 mL/min/1.73 m2 and≥60 mL/min/1.73 m2), 30 as G3 (eGFR <60 mL/min/1.73 m2 and≥30 mL/min/1.73 m2), and 2 as G4 (eGFR <30 mL/min/1.73 m2 and≥15 mL/min/1.73 m2). No significant difference in eGFR between pts with CKD G1-2 in comparison to baseline and after the first (C1), second (C2) or third cycle(C3) of tislelizumab based immunotherapy (All p >0.05). Notably, we found that eGFR improved in pts with CKD G3-4 when the first, second and third cycle completed, in comparison to the baseline.(p<0.001, <0.001, =0.002). Conclusions: Despite renal impairment is common in pts with UC, no evidence suggests that it is contraindicated for tislelizumab based treatment. More importantly, PD-1 immunotherapy may provide better nephritic benefits in patients with renal insufficiency. [Table: see text]