[Langerhans cell histiocytosis in adults]

Langerhans cell histiocytosis (LCH) is a rare disease characterized by the infiltration of one or more organs by Langerhans cell-like dendritic cells, most often organized in granulomas. The disease has been initially described in children. The clinical picture of LCH is highly variable. Bone, skin, pituitary gland, lung, central nervous system, lymphoid organs are the main organs involved whereas liver and intestinal tract localizations are less frequently encountered. LCH course ranges from a fulminant multisystem disease to spontaneous resolution. Several randomized controlled trials have enable pediatricians to refine the management of children with LCH. Adult LCH has some specific features and poses distinct therapeutic challenges, knowing that data on these patients are limited. Herein, we will provide an overview of current knowledge regarding adult LCH and its management. We will also discuss recent advances in the understanding of the disease, (i.e. the role of BRAF oncogene) that opens the way toward targeted therapies.