A RESECTED CASE OF FOCAL NODULAR HYPERPLASIA (FNH) WITH NODULAR REGENERATIVE HYPERPLASIA OF THE LIVER

We report a resected case of focal nodular hyperplasia (FNH) in the liver which was difficult to diagnose before operation. A 33-year-old man was admitted to the hospital because of a tumor of the liver, general fatigue, and liver dysfunction. Multiple nodular lesions were observed by ultrasonography, computed tomography, and angiography, which presented difficulty in diagnosis because no characteristic findings of FNH were revealed in those imaging methods. Histopathological findings of the main lesion, performed at operation, revealed FNH. In the resected specimen, multiple small and brown nodules were all diagnosed as regenerative findings. FNH is a relatively rare benign condition in the liver. When the histopathological diagnosis of FNH is made, it is permitted only to follow the progress of the lesion is it is small. But occasionally FNH can be accompanied with malignant potential or rupture with bleeding into the abdominal cavity. The lesion which is unable to be diagnosed histopathologically or enlarges rapididly may require aggressive surgical removal.