Prognostic outcomes in patients with metastatic renal cell carcinoma receiving second-line treatment with tyrosine kinase inhibitor following first-line immune-oncology combination therapy

ObjectivesThis study aimed to assess the prognostic outcomes in mRCC patients receiving second-line TKI following first-line IO combination therapy.MethodsThis study retrospectively included 243 mRCC patients receiving second-line TKI after first-line IO combination therapy: nivolumab plus ipilimumab (n = 189, IO-IO group) and either pembrolizumab plus axitinib or avelumab plus axitinib (n = 54, IO-TKI group). Oncological outcomes between the two groups were compared, and prognostication systems were developed for these patients.ResultsIn the IO-IO and IO-TKI groups, the objective response rates to second-line TKI were 34.4% and 25.9% (p = 0.26), the median PFS periods were 9.7 and 7.1 months (p = 0.79), and the median OS periods after the introduction of second-line TKI were 23.1 and 33.5 months (p = 0.93), respectively. Among the several factors examined, non-CCRCC, high CRP, and low albumin levels were identified as independent predictors of both poor PFS and OS by multivariate analyses. It was possible to precisely classify the patients into 3 risk groups regarding both PFS and OS according to the positive numbers of the independent prognostic factors. Furthermore, the c-indices of this study were superior to those of previous systems as follows: 0.75, 0.64, and 0.61 for PFS prediction and 0.76, 0.70, and 0.65 for OS prediction by the present, IMDC, and MSKCC systems, respectively.ConclusionsThere were no significant differences in the prognostic outcomes after introducing second-line TKI between the IO-IO and IO-TKI groups, and the histopathology, CRP and albumin levels had independent impacts on the prognosis in mRCC patients receiving second-line TKI, irrespective of first-line IO combination therapies.