Comparing Immuno-oncology Combination Therapy With Tyrosine Kinase Inhibitor Monotherapy for Advanced Renal Cell Carcinoma

BACKGROUND/AIM: Immuno-oncology (IO) improves the prognosis of advanced renal cell carcinoma (RCC). Since research has so far been limited to clinical trials, we herein focused on the effects of IO-tyrosine kinase inhibitor (TKI) combination therapy in real-world clinical settings. PATIENTS AND METHODS: We conducted a retrospective study on 125 patients with advanced RCC who received IO-TKI combination therapy or TKI monotherapy. Oncological outcomes were assessed by progression-free survival (PFS) and overall survival (OS), and prognostic factors for PFS and OS were investigated. We then evaluated PFS and OS based on the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC). RESULTS: The IO-TKI group showed significantly longer median PFS (18.6 months vs. 10.1 months, p=0.008) and OS (not reached vs. 34.2 months, p=0.041) than the TKI group. A multivariate analysis identified the Karnofsky performance risk score, first-line therapy (IO-TKI combination therapy or TKI monotherapy), and high C-reactive protein levels as poor prognostic factors for both PFS and OS. PFS did not significantly differ in IMDC favorable-risk patients between the groups but was significantly longer in IMDC intermediate- and poor-risk patients in the IO-TKI group than in the TKI group. OS did not significantly differ in IMDC favorable- and intermediate-risk patients between the groups but was significantly longer in IMDC poor-risk patients in the IO-TKI group. CONCLUSION: We demonstrated the advantage of IO-TKI combination therapy compared to TKI monotherapy in real-world clinical settings. However, in IMDC favorable patients PFS and OS did not significantly differ to TKI monotherapy. This may indicate the need for caution when selecting treatment options for IMDC favorable-risk patients.