[Langerhans cell histiocytosis].

Langerhans cell histiocytosis is a non-neoplastic granulomalike lesion of unknown origin; it is characterized by proliferation of reticulohistiocytic structures, polynuclear eosinophils, neutrophils, lymphocytes, plasma cells, multinucleate giant cells and Langerhans cells. In recent years, the older terms "eosinophilic granuloma" and "histiocytosis X" have been replaced by the more precise expression "Langerhans cell histiocytosis". The granuloma can be solitary and multifocal, with or without soft-tissue involvement. A specific entity is Hand-Schüller-Christian disease. Characteristic lesions in the skull are combined with exophthalmus and diabetes insipidus. These symptoms occur because of the involvement of the hypophysis. A clinically malignant form of the disease is Letterer-Siwe disease. This syndrome occurs in very small children. Dysfunction of various organs causes early death of the individual. The etiology of Langerhans cell histiocytosis is probably a dysfunction of the immune system. In the 130 cases registered at the Swiss bone tumor reference center the lesions were localized in almost all bones. The mandibula, skull, ribs and femur were the most frequently involved bones. Eighty-three patients (64%) were male, 43 (36%) female. Seventy-five percent of the lesions occurred in the first three decades of life. Ninety-three lesions were monostotic and 24 polyostotic; in 5 cases there was soft-tissue involvement, 7 had Hand-Schüller-Christian, and 1 Letterer-Siwe disease. Treatment of osseous lesions should be purely surgical; there is no need for chemotherapy in such cases. If soft-tissue involvement is diagnosed, chemotherapy should be considered. Alternatively, cortisone or interferone therapy can be administered. In our opinion there is no place for radiation therapy.