[Synchronous bilateral renal oncocytoma].

Objectives: The present study reports a case of bilateral synchronous renal oncocytoma and reviews similar cases described in the literature.

Methods: The present case was incidentally discovered in an 81-year-old female during evaluation for GI disease. The arteriogram was suggestive of oncocytoma and was confirmed by aspiration biopsy. The patient refused surgery. At 42 months' follow-up, the size and degree of invasion of both tumors remain unchanged. To our knowledge, only 20 cases of bilateral synchronous oncocytoma have been reported in the literature and only 6 of these were multifocal lesions.

Results: Renal oncocytoma, like salivary gland lesions, may spread as an advanced stage multifocal nodular oncocytic hyperplasia. Therefore it is not surprising to detect multiple synchronous or metachronous oncocytomas.

Conclusions: Bilateral renal masses are a diagnostic and therapeutic difficulty, and even more so in the absence of systemic manifestations, hereditary disorders or a family history of renal tumor.