Real world evidence from a retrospective multi-center analysis on first-line therapy for metastatic papillary renal cell carcinoma: A GUARDIANS project.

496 Background: Papillary (pRCC) renal cell carcinoma is a rare cancer. We evaluated real-world treatment outcomes of 1st line treatment in these cohorts in Germany. Methods: Data were collected retrospectively from 13 GU cancer centres in Germany. Patients (pts) with advanced or metastatic pRCC were eligible. Adverse events (AEs) were reported according to CTCAE 5.0. ORR was accessed according to local standard. Progression Free Survival (PFS) were calculated from start of treatment to progression or death. Descriptive statistics and KM-plots were utilized, where appropriate. Results: 131 suitable pts (82% male) with median age of 63 years (range 22-86) were included. ECOG 0-1 was 70%, nephrectomy was performed in 78%. IMDC scores were: 0 in 18%, ≥ 1 in 53%, missing in 29%. The most common sites of metastasis were lymphatic (66%) and pulmonary (41%) metastases. 52% patients received first-line IO-combinations (IO-IO: 18%, TKI-IO: 34%) and 40% patients TKI-monotherapy, predominantly sunitinib. AEs (all grades) with IO‐based or TKI mono therapy, were reported in 86% and 74%, CTCAE grade ≥ 3 in 46% and 22%, dose modifications were required in 35% and 26.0%. ORR and survival outcomes with median follow-up of 19 months (IQR 9-35) are described in the table. Conclusions: TKI-based therapy are frequently applied in pRCC. Our data support the use of IO+ TKI as a first-line standard for patients with pRCC. Major limitations were the retrospective data capture and short follow-up of our study. Additional analyses to tailor treatment strategies in patients with metastatic pRCC is warranted. ORR and survival outcomes of study population. Parameter All therapiesN=131 IO-ION=23 IO-TKIN=45 TKI monoN=51 OtherN=12 ORR (CR+PR) 34% 35 % 40 % 31 % 8% SD 29% 17 % 33 % 29 % 17% PD 23% 35 % 13 % 29 % 17% unknown 14% 13% 13 % 10 % 58 % mOS, months,95%-CI 32 .1 (24.4-39.9) 15.6(7.5-23.7) Not reached 27.6(19.7-35.7) 32.1(21.15-42.7) mPFS, months,95%-CI 8.5(6.5-10.4) 4.9(0.5-9.4) 9.2(3.5-15.0) 9.0(6.9-11.1) 8.5(0.0-22.8)