[en] Introduction : Langerhans cell histiocytosis is defined as a clonal neoplastic proliferation of myeloid dendritic cells that upon activation migrate from the mucosal to lymph nodes. Definitive diagnosis is made by anatomo-pathological and immunohistochemical analysis. Langerhans cell histiocytosis is rarely, yet not exceptionally, found coexisting with other malignant neoplasms, suggesting it might arise in reaction to the cytokinic secretion of malignant cells.
Case : We report the case of a 10-year-old female presenting with an isolated laterocervical lymphadenopathy and a mild general condition alteration tracing back to two months earlier. Nodal biopsy was performed and revealed concomitant involvement by Langerhans cell histiocytosis and Hodgkin lymphoma. Treatment of lymphoma led to the disappearance of the whole symptomatology.
Discussion : Literature beholds reports of 30 cases of the simultaneous occurence of Hodgkin lymphoma with Langerhans cell histiocytosis, which is more than fortuitous regarding the low incidence of both diseases. A common etiology could explain such an association, but it might also be possible that background inflammatory cells of Hodgkin lymphoma stimulate the proliferation of Langerhans cells, making it a reactive process when occurring simultaneously with other neoplasms.
Clinicians should thus be aware of the possibility of this association and carefully exclude any other life-threatening malignant proliferation when confronted to apparently isolated Langerhans cell histiocytosis.
