ABSTRACT
Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the proliferation of specialized bone marrow-derived Langerhans cells (LCs) and mature eosinophils. Its etiology is unknown but it could be due to antigenic stimulus of an infectious, genetic abnormality, deregulated immune response, or even clonal origin. Clinical presentation may be localized and systemic, invading skin, lungs and bone in adult, and bone marrow and lymph node in children. Obtaining a biopsy that yields cells that are morphologically and immunohistochemically compatible with Langerhans cells, can make a definitive diagnosis of LCH. Poor prognosis factor include advanced age, disease extent and systemic organ abnormality. Conventional treatment of LCH is with surgery, radiotherapy, chemotherapy and steroid injections, alone or in combination. Spontaneous regression of localized disease has also been reported.
