Nivolumab plus ipilimumab (NIVO-IPI) is one of the treatment standards for previously untreated clear cell renal cell carcinoma (RCC). Furthermore, the 20% progressive disease (PD) criterion as the best objective response was reportedly higher in the NIVO-IPI clinical trial than that in the other immune checkpoint inhibitor (ICI) combined regimens.1-4 There is an urgent need for predictive biomarkers for clinical outcomes and early detection of PD in NIVO-IPI therapy.