Trends in real-world outcomes of patients with metastatic renal cell cancer in the recent treatment era: A single institution analysis

Background Systemic therapy for metastatic renal cell cancer (mRCC) has changed significantly due to randomized controlled trial results. We investigated whether these changes affect real-world outcomes and clarified factors associated with treatment outcomes in patients from a single institution outside of clinical trials. Methods We retrospectively reviewed records of mRCC patients treated at Osaka International Cancer Institute between January 2005 and May 2024. Between-group analysis of progression-free survival (PFS) and overall survival (OS) by Kaplan-Meier comparison and identification of survival-associated factors by univariate and multivariate analyses were performed. Patients assumed ineligible for clinical trials were analyzed in subgroups according to any of Eastern Cooperative Oncology Group performance status > 1, hemoglobin level < 9.0 g/dL, estimated glomerular filtration rate < 40 mL/min/1.73 m ² , platelet count < 100,000/µL, neutrophil count < 1500/µL, nonclear cell histology, or brain metastasis. Results In total, 320 patients were evaluated: 2005–2009, n = 58; 2010–2014, n = 77; 2015‒2019, n = 86; and 2020‒2024, n = 99. Significant between-group differences were observed for median PFS (7 vs. 8 vs. 12 vs. 20 months; p = 0.0048) and OS (45 vs. 38 vs. 67 vs. 52 months; p = 0.0206). Multivariate analysis revealed that first-line or subsequent-line immune checkpoint inhibitor (ICI) use was an independent factor for OS (HR: 0.28, p < 0.0001). Even among 112 (35%) trial-ineligible patients, multivariate analysis demonstrated that the use of first-line or subsequent-line ICI was an independent factor for OS (HR: 0.24, p < 0.0001). Conclusion Over time, treatment outcomes appeared to have improved with real-world treatment for mRCC, with use of ICIs being related to improvements in treatment outcomes.