Calcification in focal nodular hyperplasia: A new problem for differentiation from fibrolamellar hepatocellular carcinoma

PURPOSE: To describe calcification in focal nodular hyperplasia (FNH) of the liver, which poses a new problem for the differentiation of FNH from fibrolamellar hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ultrasound, computed tomography, and magnetic resonance imaging findings of 357 FNH lesions diagnosed in the past 5 years in 295 patients (274 female, 21 male; aged 14-72 years) were retrospectively reviewed with emphasis on intralesional calcification. RESULTS: Calcifications were seen in five FNH lesions (1.4%) as small, solitary spots located centrally or peripherally within the lesions. Morphologic features of these calcifications were similar to those of calcifications in two of six fibrolamellar HCCs in the same period. CONCLUSION: Calcification in FNH is a rare and atypical finding that poses further difficulty for differentiation from fibrolamellar HCC.