A case of progressive multiple focal nodular hyperplasia with alteration of imaging studies

Focal nodular hyperplasia (FNH) of the liver is a lesion characterized by a well circumscribed region of hyperplastic liver tissue with stellate fibro sis, The pathogenesis of the lesion is unknown but various authors consider that FNH may be a response to a preexisting vascular abnormality. We exper ienced a case of progressive multiple FNH, in which the hemodynamic change as shown by imaging modalities, may support this hypothesis. The patient, a 38-yr-old woman, was found by chance to have multiple portal venous shunts and multiple FNH in both lobes of her liver. Because of their benign chara cteristics, we followed the nodules periodically without any special treatm ent. After about 4 yr, the nodules increased both in size and number. In ad dition, digital subtraction angiography showed that the diameter of the art ery had become larger. The hemodynamic change revealed by imaging studies i n this case supports the hypothesis that one of the pathogens of FNH is a s econdary hepatocellular response to arterial hyperperfusion caused by some vascular malformations. (C) 1998 by Am. Cell. of Gastroenterology.