Diagnosis:
Reticulin Stain for Hepatocellular Carcinoma
• Reticulin stain is part of the routine special stain panel of liver stains ordered in the work-up of liver diseases.
• Reticulin stain not only demonstrates the underlying microscopic architecture (including portal tract and sinusoidal collagen distributions and liver cell plate thickness) but also is useful in identifying regenerative hyperplasia, regions of developing parenchymal nodularity, and cirrhosis.
• In HCC, the tumor has a “paucireticulin” pattern, which is diagnostically useful in distinguishing carcinoma from underlying normal liver tissue and from liver cell adenoma, both of which show a preserved reticulin pattern.
• In cases in which reticulin stain does not show a paucireticulin pattern but HCC is still suspected, immunostains (including CD34, glypican-3, glutamine synthetase, and heat shock protein 70) may provide additional help in establishing a correct diagnosis.
