Mallory bodies in scar adenocarcinoma of the lung

A 75 year old man presented with metastatic carcinoma of the brain. At autopsy a primary scar adenocarcinoma of the lung was found. By light microscopy the cytoplasm of the tumor cells was seen to contain hyalin masses with tinctorial properties identical to those of the Mallory bodies seen in human alcoholic liver disease and in hepatocellular carcinoma. The hyalin stained positively with anti-Mallory body antibody by the peroxidase antiperoxidase technique, and had the characteristic filamentous and granular amorphous appearance of alcoholic hyalin by electron microscopy. Our observation is of interest in light of recent information relating Mallory bodies to prekeratin, and vitamin A deficiency to lung cancer.