Langerhans Cell Histiocytosis on Fine Needle Aspiration Cytology

175 LCH is a rare disease affecting predominantly children and young adults. LCH is considered a neoplasm of the mononuclear phagocytic immunoregulatory system. It is characterized by clonal proliferation of Langerhans cells (LCs). LCH has three categories: eosinophilic granuloma (solitary and most common), Hand-Schuller-Christian disease (multifocal unisystem form) and Letterer-Siwe syndrome (multifocal multisystem form)1,2. The diagnostic cytological features of LCH include high cellularity composed of sheets of characteristic Langerhans cell with large kidney-shaped nuclei admixed with eosinophils, neutrophils, macrophages, and lymphocytes.