PDCD1 and nonpapillary renal cell carcinoma: Although the anti-angiogenic therapies have significantly improved the overall survival of the patients with advanced or metastatic ccRCC over the past decade, the immune checkpoint blockade therapy (ICBT), such as anti-programmed cell death 1 (anti-PD-1) therapy, has also been shown to be efficacious in metastatic RCC patients once anti-angiogenic therapy fails [11–13].