Which factors help to determine the long-term response to first-line tyrosine kinase inhibitors in patients with metastatic renal cell carcinoma: A Turkish multicenter study

In patients with metastatic renal cell carcinoma (mRCC), although immune checkpoint inhibitor (ICI)–tyrosine kinase inhibitor (TKI) combinations or ICI–ICI combinations are typically recommended as first-line treatments, access to these combinations is often limited in developing countries. Therefore, there is a need for predictive markers to identify patients who may achieve long-term responses with single-agent TKIs. Our study aimed to identify such predictive parameters. This multicenter, retrospective study included patients diagnosed with mRCC who received first-line treatment with sunitinib or pazopanib. Patients who did not experience disease progression for 36 months or longer were classified as long-term responders. We investigated the clinical and pathological characteristics predictive of long-term response in these patients. A total of 320 patients from four hospitals were included, with a median age of 60 years (range of 20–89 years). According to the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk classification, 109 patients were in the favorable risk group and 211 in the intermediate-poor risk group. The median progression-free survival (PFS) and overall survival (OS) for all patients were 12.5 months and 76.4 months, respectively. In the long-term responders’ group, the median PFS was 78.4 months. For the entire group, prior nephrectomy, an Eastern Cooperative Oncology Group (ECOG) performance status (PS)