Benign tumors in the liver include hepatocellular adenomas, focal nodular hyperplasia, bile duct adenomas, and benign vascular lesions which are often biopsied. Distinction of hepatocellular adenoma from carcinoma can be challenging on biopsy; the diagnosis of malignancy is aided with the reticulin stain that shows thickened cell plates and loss of reticulin, and may also be aided by immunohistochemistry (IHC) staining.
