Single-system Langerhans Cell Histiocytosis (LCH) exhibits extensive eosinophil infiltration as well as occasional necrosis and cyst/cavity development; however the origin of the necrosis is unknown. Because the involvement of eosinophils in necrosis in single-system LCH has not been studied previously, we evaluated it pathologically.
Due to the proliferation of histiocyte-like cells, which have recently been proven to be Langerhans cells, Langerhans Cell Histiocytosis (LCH) incorporates eosinophilic granuloma, Hand-Schüller-Christian illness, and Letterer-Siwe disease. The BRAF V600E mutation is a significant genetic component in LCH, and a new name (inflammatory myeloid neoplasia) was coined.