Rare malignant neoplasm of dendritic LANGERHANS CELLS exhibiting atypical cytology, frequent mitoses, and aggressive clinical behavior. They can be distinguished from other histiocytic and dendritic proliferations by immunohistochemical and ultrastructure studies. Cytologically benign proliferations of Langerhans cells are called LANGERHANS CELL HISTIOCYTOSIS.

Synonyms: Langerhans Cell Sarcomas, Langerhans Cell Sarcoma, Sarcoma, Langerhans Cell, Sarcomas, Langerhans Cell