Hepatocellular adenoma-like lesion of placenta is an extremely rare, benign non-trophoblastic lesion. Only a handful cases have been reported to date, and the exact nature of this benign lesion is not well understood. It is usually composed of a nest of cells resembling foetal hepatocytes without portal tracts, forming a subchorionic mass. Here, we report a case of an incidental finding of hepatocellular adenoma-like lesion of placenta in a 20-year-old female with a history of previous molar pregnancy. The hepatocellular origin of the lesion is confirmed with immunohistochemistry. It has shown positive immunohistochemical staining for HepPar1 and negative staining for cytokeratin, BCL-2, D2-40, Melan-A, and S100. No beta-catenin nuclear staining is observed, confirming it to be a non-beta-catenin mutated hepatocellular adenoma.
Uemura et al. (Sun,) studied this question.