[Oncocytomas of the kidney. Analysis of current knowledge and creation of a study group]

Typical oncocytomas are easily recognized. Nevertheless, in recent years, some cases of atypical oncocytomas much more difficult to identify, have been published in French and English medical literature. To further complicate the matter, the tumors are sometimes described as benign and sometimes as malignant. To try to clarify such discrepancies, this article will first set forth the current knowledge, and second provide the basis for a subsequent study designed to simultaneously resolve the histologic and prognostic dilemma.