Biopsy-confirmed spontaneous resolution of orbital langerhans cell histiocytosis

A 17-year-old boy presented with a left upper lid swelling, headaches and diplopia. An orbital computerized tomography (CT) scan showed a mass in the left lacrimal fossa eroding bone and extending into the temporalis fossa and intracranially. An urgent biopsy without curettage was carried out and showed Langerhans cell histiocytosis. He was otherwise well and no other lesion was found. He was therefore observed and reviewed regularly. During follow-up it was noted that the mass was reducing in size. Five months after the initial biopsy a further procedure, involving curettage and an intralesional steroid, was carried out at a tertiary referral center. Histology of the material obtained showed no remaining evidence of Langerhans cell histiocytosis. Spontaneous resolution of orbital Langerhans cell histiocytosis has been described clinically and radiologically. This is the first case of spontaneous resolution to be confirmed histologically.