Benign Hepatocellular Tumors: A Multidisciplinary Approach

Copyright © 2013 Paulette Bioulac-Sage et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This special issue is an attempt to cover some new aspects concerning benign hepatocellular tumors: focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA). In this special issue, we were fortunate enough to have editors from different countries (France, Italy, The Netherlands, and USA) and from different disciplines (liver pathology, liver radiology, liver surgery, and hepatology) who have contributed 6 papers and 5 contributors from academic centres involved in benign hepatocellular tumors, namely, liver pathologists, radiologists, and molecular biologists from different continents: Europe, North America, and Asia. Concerning FNH, if their diagnosis is mainly made by radiologists, some particular cases required a biopsy or even resection. When standard pathological features are atypical, the diagnosis is greatly facilitated by immunohistochemistry, particularly the characteristic pattern of glutamine synthetase (GS), in biopsy as well as surgical specimens, as described by the Bordeaux group. HCA is the main topic of this issue. This benign rare liver tumor came to medical attention in 1973 when it became clear that oral contraceptives introduced in the USA in 1960 were the main agents responsible for the occurrence of HCA. The first complication identified was bleeding, which was occasionally life threatening, was often the first manifestation of tumor, and often led to surgical resection. The second complication, hepatocellular carcinoma (HCC) transformation, reinforced a surgical approach to treatment in spite of the fact that malignant transformation remains a subject of controversy. HCA is a worldwide problem with a clear difference in incidence between Europe and Asia. This difference is mainly explained by the different methods of contraception in the world. In Europe oral contraceptives (OC) are taken by 54, In a study from Japan published in this issue, only 2 of 13 cases of HCA described were found in women taking OC. Presently there is no data concerning the influence of the OC generation on the incidence of HCA. It was thought that the lower levels of estradiol should decrease the risk of HCA. This was not observed. The possible explanation comes from the identification of novel risk factors, namely, obesity and metabolic syndrome. Exploring the combined experience of US centers, publications reporting HCA in the US were identified through a PubMed search …