Pathologic features of renal cortical tumors.

Our better understanding of the morphologic spectrum of renal cortical tumors has resulted in a clinically more relevant classification of these tumor types. We now recognize that "granular cell" and "sarcomatoid" renal cell carcinoma are only nonspecific descriptors, and that such features are seen in a variety of types of renal tumors. The authors believe that the recently gained knowledge about molecular-driven antigen expression will play an important role in the characterization, development, and evaluation of targeted therapies in kidney cancer in the coming years.