This systematic review and meta-analysis aims to provide a pooled analysis of the available efficacy data of anti PD1/PDL-1 -based therapy vs. sunitinib in patients with sarcomatoid RCC (sRCC) With the limitations imposed by data availability, exploratory analyses were performed to assess differences in efficacy of anti PD-1/PD-L1-based therapy vs. sunitinib between sarcomatoid and unselected/non-sarcomatoid RCC patients, as well as establishing the potentially optimal anti PD-1/PD-L1-based regimen against sRCC. This evidence concerns the gene CD274 and renal cell carcinoma.