A case of Langerhans cell histiocytosis of the cranial bone

We report a case of Langerhans cell histiocytosis of the occipital bone in a 6-year-old boy. Imprint smears of the lesion showed scattered Langerhans cells with convoluted nuclei and pseudopodia-like cytoplasmic projections against a background of eosinophils, neutrophils, lymphocytes, and multinucleated histiocytic giant cells. We diagnosed the lesion cytologically as Langerhans cell histiocytosis, confirmed by histological findings. Pseudopodia-like cytoplasmic projections are considered an additional typical cytological finding for Langerhans cells in imprint smears.