Clinical, Radiological and Pathological Exploration of Focal Nodular Hyperplasia of Liver Reported in Korea

BACKGROUND/AIMS: Focal nodular hyperplasia (FNH) is mandatory to be differentiated from other hepatic tumorous conditions such as hepatocellular carcinoma and adenoma. The purpose of this study was to explore the clinical radiological and pathological features of FNH cases reported in Korea. METHODS: We have searched the journals from the web site "http://koreamed.org" using keywords "focal nodular hyperplasia" and "liver" - total of 38 cases of FNH 37 cases from 17 published articles and one case from our experience confirmed histologically were reviewed and analyzed. RESULTS: Thirty eight cases were diagnosed between gestational age of 36 weeks and 67 years. Seventeen female patients (45%) had no history of taking oral contraceptives. Twenty cases (52.6%) experienced clinical symptoms such as abdominal pain and palpable mass. Computed tomography revealed contrast-enhancement in 34 nodules (85%) and typical central stellate scar in 9 (22.5%) of 40 nodules. Magnetic resonance imaging showed T1 weighted low signal in 18 (60%) and T2 weighted high signal in 22 (73.3%) of 30 nodules. Six (60%) of 10 cases showed hypervascular staining on hepatic angiography. Among 38 cases 32 (84.2%) cases had single nodule and their mean size was 3.9 cm (0.5-16 cm). Pathologically fibrous septa proliferation of bile ductules and arterial wall thickening were seen in most cases. CONCLUSIONS: Of all the FNH cases reported in Korea there were some differences in clinical aspects of sex ratio accompanying clinical symptoms and relationship with oral contraceptives compared with previous reports. Further prospective studies are needed by means of nation-wide clinical survey and analysis.