This is the classic clear cell histologic appearance of a renal cell carcinoma: the neoplastic cells have clear cytoplasm and are arranged in nests with intervening blood vessels. This microscopic appearance is why they are often called "clear cell carcinomas". Mutation of the VHL gene may be found.
The less common papillary variant of renal cell carcinoma is shown below. Note the eosinophilic cytoplasm. Mutation of the MET gene may be present.