Prognostic model of upfront cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with immune checkpoint inhibitors and/or targeted agents

Abstract

Introduction and objectives: The aim of this study was to investigate prognostic factors and to establish a prognostic model using them for upfront cytoreductive nephrectomy (CN) in patients with metastatic renal cell carcinoma (mRCC) treated with immune checkpoint inhibitor (ICI) and/or tyrosine kinase inhibitor (TKI).

Materials and methods: Two hundred eleven patients who were diagnosed as mRCC at initial diagnosis and were treated with TKI and/or ICI were classified into 2 groups: those undergoing CN (upfront CN group, 117 cases) and those who initially underwent systemic therapy (non-upfront CN group, 94 cases). In the upfront CN group, the patients' background and overall survival (OS) were compared with those in the other two groups, and prognostic factors were analyzed. A prognostic model of the upfront CN group was established.

Results: The median of the observation period for the upfront CN group was 25 months. The rates of patients with clear cell histology, with a Karnofsky performance status (KPS) of ≥ 80%, with a single metastatic organ, with a normal pretreated C-reactive protein level, and with an intermediate risk according to the International mRCC Database Consortium (IMDC) model were significantly higher than those in the non-upfront CN group (87.2% and 30.9%, p < 0.0001; 92.3% and 77.7%, p = 0.0025; 41.9% and 24.5%, p = 0.0080; 47.9% and 13.8%, p < 0.0001; 66.7% and 45.7%, p = 0.0023, respectively). The 50% OS in the upfront CN group was 33.1 months, significantly better than that in the non-upfront CN group (11.1 months, p < 0.0001), and these results were consistent regardless of their prognostic risk level. Multivariate analysis showed that multiple metastatic organs and a KPS of < 80% were independent predictive factors for OS (hazard ratio: 1.653 and 2.995, p = 0.0339 and 0.0054, respectively). Using these two parameters to stratify the upfront CN group, the 50% OSs in cases with no risk factors, in those with one factor, and in those with two factors were 43.4 months, 29.1 months, and 7.7 months, respectively (p < 0.0001).

Conclusion: The upfront CN group was able to be stratified by our prognostic model into three subgroups with different prognoses. This model can provide useful information for making decisions in consideration of upfront CN in patients with mRCC.

Keywords: Cytoreductive nephrectomy; Overall survival; Prognostic factor; Renal cell carcinoma.