Mitotic histiocytes and intranuclear Langerhans cell granules in histiocytosis X.

Several mitotic histiocytes containing Langerhans cell granules were found in the lymph nodes of Letterer-Siwe disease. Some histiocytes of Hand-Schüller-Christian disease contained Langerhans cell granules within the nuclei. These Langerhans cell granules were not in 'nuclear pseudo-inclusions,' but were freely scattered inside the nuclei. We suggest that the Langerhans cell granules may get trapped in the nucleus during mitosis, since several investigators have suggested that mitosis causes other intranuclear organelles to get trapped. We also speculate that cells containing Langerhans cell granules may divide and increase by mitosis.