Genomic analysis of focal nodular hyperplasia with associated hepatocellular carcinoma unveils its malignant potential: a case report

Plain language summary Focal nodular hyperplasia (FNH) is a lesion resulting from the abnormal growth of liver cells. It is typically considered a benign tumor that does not become malignant. In rare cases, FNH may occur alongside malignant hepatocellular carcinoma (HCC). In these cases, it is not known whether the malignant HCC may derive from the benign FNH. In this study, we reported on the analysis of a 74-year-old female patient with co-occurring FNH and HCC. We found that the FNH and HCC lesions were in fact genetically related, suggesting that the FNH gave rise to the HCC lesions. Furthermore, we found multiple cell populations within the FHN lesion that may be precursors to the HCC lesions suggesting that, in rare cases, FNH may be capable of progressing to malignant HCC. These findings may help to refine the surveillance strategy for these lesions.