Abstract:

Langerhans cell histiocytosis(LCH) is an inflammatory myeloid malignancies with MAPK pathway activation mutations detectable in nearly all patients and a pronounced inflammatory state. The clinical manifestations of LCH are diversity, the most common involved organs included Bones, lungs, pituitary, ect. The primary diagnosis of LCH depends on histopathologic review of lesional tissue biopsy; the gold standard for diagnosis were expression of Cd207 (Langerlin) in immunohistochemistry and birbeck granules(BGs) by electron microscopy. LCH can be devided into localized single-system disease(SS-s), multiple sites within one single system (SS-m), and multisystem(MS) disease according to the scope of clinically involved organs. In terms of clinical classification, Local therapies may be sufficient for SS-s patients, systemic therapies might be better for SS-m or MS patients.

Key words: histiocytosis,langerhans-cell, MAPK pathway, diagnosis, treatment