Rupture and hemorrhage of hepatic focal nodular hyperplasia

Although adenoma and focal nodular hyperplasia (FNH) are both benign liver lesions, adenomas are associated with a risk of rupture and malignant degeneration. This had led to the general recommendation of resection of adenomas. However, FNH rarely ruptures or becomes malignant, and a nonoperative approach has been adopted by most hepatobiliary centers when the diagnosis of FNH can be made with reasonable certainty. There are only two previous reports of rupture of FNH in the English literature; we present a third case of FNH with spontaneous rupture and hemorrhage. An 18-year-old healthy Caucasian woman presented with sudden onset of severe RUQ pain. She had never been pregnant, nor used oral contraceptive agents, and had not sustained major trauma. Her abdominal exam revealed RUQ tenderness on palpation. Hepatic biochemical tests, CBC, and coagulation tests were normal. Her hematocrit of 44% fell to 31% over 48 hours. CT scan revealed right anterior lobe and left medial segment hypodense liver lesions (4-5 cm) as well as hemoperitoneum and angiography revealed hypervascular lesions. At laparotomy, two tan fibrous subcapsular masses were excised. Pathology showed a central stellate scar in both lesions with several nodules surrounding the central scar on microscopic section, characteristic of FNH. There was evidence of hemorrhage in one lesion. Significant symptoms are an indication for resection of FNH lesions. However, most patients with FNH are asymptomatic and have a normal physical exam. The natural history of these lesions is enigmatic, and the indications for surgery are still evolving. This report emphasizes that a small risk of rupture clearly exists.(ABSTRACT TRUNCATED AT 250 WORDS)