Juvenile xanthogranuloma presenting as a large neck mass and ocular complications: a diagnostic and therapeutic dilemma.

Juvenile xanthogranuloma is a non-Langerhans cell histiocytosis that originates from dendritic cells. Dendritic cells can accumulate in the skin of the head, neck, trunk, arms and legs. They may also involve other tissues such as the bones, lung, liver, heart, bone marrow, central nervous system, spleen and large intestine in rare cases. We report a rare case of juvenile xanthogranuloma in a 16-year-old girl who presented with a neck mass and left-sided ptosis 2.5 months previously. Excisional biopsy of the neck lesion revealed proliferated histiocytes admixed with numerous eosinophils and multinucleated giant cells that simulate eosinophilic granuloma; however, the histiocytes were negative for CD1a, CD123 and S-100 protein and positive for CD68 and CD14. The course of the disease led to treatment of the patient with chemotherapy, followed by low-dose radiotherapy.