CTLA4 and renal cell carcinoma: PD-L1 expression is the only broadly used predictive biomarker, but in ccRCC it is of limited clinical use.10–13 However, patients with ≥1% PD-L1 expression seem to benefit particularly from intensified immunotherapy with nivolumab plus ipilimumab.3 In our multicenter RCC-ICB Cohort, CTLA4 promoter hypomethylation outperformed PD-L1 CPS, which had no significant predictive value in our cohort.