[Orbital location of multivisceral Langerhans-cell histiocytosis].

Langerhans-cell histiocytosis is a rare disease accounting for less than 1% of orbital tumours. We report the case of an 18-month-old infant presenting with exophthalmos of the left eye lasting for 3 months in a context of deterioration of the general condition, polydipsia, and polyuria. The computed tomographic scan revealed an orbital cellular mass with a lytic bone lesion within the orbital roof and infiltration of frontopalpebral soft tissue. In addition, other secondary lesions were found at the skull, ribs, skin, liver, and spleen. The cytological study after biopsy showed infiltrates of histiocytes derived from Langerhans cells. Because the disease was multivisceral, the child was treated with chemotherapy (vinblastine) combined with a steroid and progressed well. At 30 months of follow-up, there was no evidence of recurrence or systemic involvement.