Focal nodular hyperplasia of the liver

org/10.4322/acr.2014.033 A benign, non-neoplastic, reactive growth of the liver, focal nodular hyperplasia (FNH) of the liver was first clearly described by Edmondson in the 1950’s, although there are various prior reports that likely represent the same lesion. A variety of synonyms have been applied including focal cirrhosis, pedunculated adenoma, solitary hyperplastic nodule, mixed adenoma, hamartoma and hamartomatous cholangeiohepatoma. FNH is the most frequent benign, solid hepatic tumor and, after hemangioma, the second most common benign lesion.1 In an autopsy series comprising 96,625 patients, Craig et al.2 identified 8 % of non-hemangiomatous hepatic lesions as FNH. The various labels applied over the years hav