Nodular regenerative hyperplasia of the liver. Report of six cases and review of the literature.

The authors report the cases of 6 adult patients suffering from nodular regenerative hyperplasia of the liver, an uncommon lesion characterized by small-sized hepatocytic nodules scattered throughout the liver, with no or slight fibrosis. The histological recognition of nodular regenerative hyperplasia of the liver was easy on large specimens taken intraoperatively, but was difficult or impossible on small specimens such as those provided by needle biopsy. In all of the patients of this series, the main consequence of nodular regenerative hyperplasia of the liver was portal hypertension. In this series, nodular regenerative hyperplasia of the liver was not associated with rheumatoid arthritis, whereas such an association has been noted in most of the cases previously reported. The etiology and pathogenesis of nodular regenerative hyperplasia of the liver is unknown.