Langerhans Cell Histiocytosis Evolving into Juvenile Xanthogranuloma: Two Linked Entities

Abstract

Background: Langerhans cell histiocytosis (LCH) represents a myeloid clonal proliferation that involves the skin and other organs. Occasionally, cases of LCH evolve into juvenile xanthogranuloma (JXG). Case Presentation: A 7-month-old boy presented with an itchy, flaky rash resembling seborrheic dermatitis affecting the scalp and eyebrows. The lesions started at 2 months old. On physical examination, there were reddish/brown lesions on the trunk, denuded areas on the groin and neck, and a large lesion behind his bottom teeth. In addition, there were thick white plaques in his mouth and thick whitish material in both ears. A skin biopsy showed features of LCH. Radiologic examination demonstrated several osteolytic lesions. Chemotherapy produced marked improvement. A few months later, the patient developed lesions with clinical and histologic features of XG. Conclusion: A possible association between LCH and XG is explained by lineage maturation development. Chemotherapy may play a role in modifying the production of cytokines that enhance the transformation or ‘maturation’ of Langerhans cells into multinucleated macrophages (Touton cells) characteristic of a more favorable proliferative inflammatory condition.