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[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.