[Hepatic adenoma and focal nodular hyperplasia: difficult differential diagnosis. Presentation of a case of focal nodular hyperplasia].

Hepatic adenoma and focal nodular hyperplasia are unfrequent benign lesions of the liver with individual histologic characteristics, but not always clinically distinguishable. The main difference is the intratumoral or intraperitoneal bleeding risk (high in adenoma and virtually zero in focal nodular hyperplasia). Surgery is the elective treatment for the first, while a more conservative attitude is allowed for the second. We present the case of a woman with an hepatic mass that clinically and radiologically seemed to be an adenoma. An atypical hepatectomy was done uneventfully. The examination of the specimen showed shaw focal nodular hyperplasia. We review the diagnostic and therapeutic controversy between these entities, because only the histologic examination of the entire surgical specimen could demonstrate the real nature of the lesion.