Whats the clonality status and allelotype of focal nodular hyperplasia?
Focal nodular hyperplasia (FNH) is a lesion found in an otherwise normal liver, and is considered to be parenchyma overgrowth responsive to increased blood flow secondary to vascular malformations. While its clinical outcomes are believed to be different from hepatocellular adenoma and carcinoma, its pathogenesis is largely unclear and its distinction from hepatocellular adenoma is sometimes difficult. A research article published on 7 October in the World Journal of Gastroenterology addresses this question. The authors examined 12 FNH lesions via histological approaches, X-chromosome inactivation and allelotyping assays, using 12 hepatocellular adenomas and 22 hepatocellular carcinomas as references. Nodules of different types were isolated from FNH by microdissection and tested for clonality and genetic alterations. Nodules of altered hepatocytes (NAH), the putative precursors of both hepatocellular adenoma and carcinoma, were found in all the FNH lesions. Polyclonality was revealed
