Pictures of focal nodular hyperplasia and hepatocellular adenomas

Figure 6 HNF1A mutated hepatocellular adenoma microscopic typical features. A: Woman born in 1955; surgery in 2010 for an HCC (6 cm) developed on a non fibrotic liver. Discovery of another small nodule on the surgical specimen. No oral contraceptives; BMI 24.1 kg/m². HE: typical aspect of HNF1A mutated hepatocellular adenoma (H-HCA): nodule with lobulated contours, made of benign hepatocytes with diffuse steatosis; some congestive areas ( arrowhead); sharp contrast with non steatotic surrounding liver. The diagnosis was confirmed by immunohistochemistry. B, C: Woman born in 1952; abdominal pain; imaging: nodule 1.8 cm, no firm diagnosis by magnetic resonance imaging. Oral contraceptives, 27 years; BMI 22.0 kg/m². Tumorectomy in 2008. B: Nodule composed of benign, clear hepatocytes, sometimes steatotic, separated by thin strands of atrophic hepatocytes (arrow). C: Same nodule seen at higher magnification. Although clear hepatocytes are not the hallmark of H-HCA, the lobular pattern is very characteristic. It consists of steatotic or clear hepatocytes arranged in a lobular pattern separated by tumoral, atrophic, not steatotic hepatocytes. Commonly, arterioles/small arteries are seen in this space (not shown on this micrograph). The diagnosis was confirmed by immunohistochemistry.