EPAS1 and nonpapillary renal cell carcinoma: Clear cell renal cell carcinoma (ccRCC), the most common form of RCC, is characterized by inactivation of the Von Hippel-Lindau (VHL) tumor suppressor gene and subsequent stabilization of hypoxia-inducible factors (HIF-1α and HIF-2α), which is in turn promote angiogenesis, cell migration, and increased metabolism [3].