Hepatocellular adenoma and nodular regenerative hyperplasia of the liver in a young man.

A 26-year-old man had a massive intraabdominal hemorrhage from a hepatocellular adenoma (HCA). The tumor arose within a liver that demonstrated generalized nodular regenerative hyperplasia. The patient had no factors predisposing to either HCA or nodular regenerative hyperplasia (NRH) of the liver. Although rare, HCA should be included in the differential diagnosis of spontaneous intraperitoneal hemorrhage even in young men. The coexistence of HCA and NRH of the liver in this patient may indicate a common pathogenesis.