The mutational burden of targeted genes significantly correlated with overall survival after targeted therapy in metastatic renal cell carcinoma.

643Background: This study aimed to find the correlation between tumor mutation burden and systemic first line therapeutic response in metastatic tissue samples from patients with metastatic renal cell carcinoma (mRCC). Methods: Between 2005 and 2017, 168 triplet-tissue block samples from 56 mRCC patients were selected for targeted gene sequencing (TGS) using the 88 targeted genes from the National Cancer Center, Korea (NCC) kidney cancer panel. The patients’ medical records, including therapeutic responsive profiles with overall survival (OS) to first-line targeted therapy, were evaluated with the mutational burden of triplet tissue samples using 88 TGS. A few significant target genes associated with therapeutic response towards targeted therapy were identified after comparing the mutational burden of positive for all three blocks and one or two positive blocks (p-value < 0.05). Results: The median PFS for the first-line targeted therapy and OS were 8.7 and 42 months, respectively. MSKCC and Heng risk cri...