Focal nodular hyperplasia of the liver. A clinicopathologic study and review of the literature
Lymphoma, Large B-Cell, Diffuse
The clinical records and biopsy proven material from 20 cases of focal nodular hyperplasia were reviewed, and the English literature on the subject was surveyed. Most of the 20 patients were women of childbearing age. A history of oral contraceptive use was obtained in 5 cases. 3 of the patients were males. The condition was an incidental finding in all 20 cases. Liver function tests were normal. The histopathologic findings are distinguishable from liver cell adenoma. Nodular aggregations of normal hepatocytes with foci of intranodular bile duct proliferation were seen. The nodules blended into the surrounding liver parenchyma while liver cell adenomas are encapsulated masses without the central scar or radiating fibrous septa. Figures illustrate histologic findings of focal nodular hyperplasia. A review of the English literature revealed only 82 acceptable cases of focal nodular hyperplasia, 12 of which were necropsy findings or lacked clinical data. A few cases have been among males. The association with use of oral contraceptives may be only coincidental. Only 29 of the 82 were 18 years of age or older, 2 of whom were women. Mean age of adult males was 42 years and of adult females, 34 years. In 16 patients the focal nodular hyperplasia had been an incidental finding but in 13 there had been either an abdominal mass or symptoms of abdominal discomfort, nausea, and vomiting. Focal nodular hyperplasia is a benign lession. Removal is unnecessary except in large tumors. It is possible that hormonally related vascular changes may lead to rupture of the lesion with intraabdominal hemorrhage.