Langerhans cell histiocytosis in adults: a case report and review of the literature

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferative disease of histiocyte-like cells that generally affects children. Immunohistochemistry is essential to obtain the correct diagnosis, and treatment protocols are controversial. OBJECTIVE: Langerhans cell histiocytosis (LCH) is easy to be misdiagnosed because of its various clinic features and laboratory results. This research focused on the clinicopathological, histopathological, immunohistochemical and other features of LCH and aimed to analyze LCH clinical features for improving diagnosis and decreasing misdiagnosis rate. CASE REPORT: A case of rare adult LCH was reported and the clinicopathological features were summarized by literature review. The multifocal form of this case includes diabetes insipidus, exophthalmos and mucocutaneous lesions in axillae and anogenital regions, such as infiltrated nodules, extensive coalescing, scaling, crusted papules and ulcerated plaques. The Langerhans cells diffusely infiltrated in the dermis and the tumor cells were positive for CD1a and S-100 expression. The diagnosis was Langerhans cell histiocytosis based on the pathological and immunohistochemical changes. CONCLUSION: LCH has high rate of misdiagnosis and definitive diagnosis depends on pathological biopsy and X-ray examination. The prognosis is related to the onset age and the quantity of affected organs. Although specific therapeutic approach hasn't been well established, combined chemotherapy for multisystem lesions and surgical operation or radiotherapy for unifocal lesions may improve the therapy.