Langerhans cell histiocytosis of the orbit: pediatric case series.

Objective: To describe the clinical, imaging characteristics, and treatment of pediatric orbital Langerhans cell histiocytosis (LCH).

Design: Retrospective case series.

Participants: Children with orbital LCH.

Methods: Children with orbital LCH who presented to 4 different centres over the past 10 years. Demographic details, presenting features, imaging, histopathology, immunohistochemistry, and management outcomes were analyzed.

Results: Sixteen patients were reviewed. The mean age of presentation was 6.56 ± 4.38 years (range, 1-18 years). Eyelid swelling was the most common presenting feature (13, 81%), followed by proptosis (1, 5%), eyebrow swelling (1,5%), and temple swelling (1, 5%). Imaging revealed superior orbital lesions with osteolytic defects of the orbital roof in 13 (72.2%) patients. Frontal and zygomatic bones were the most commonly affected. All the orbital lesions were extraconal. All patients in the study were diagnosed with LCH from orbital tissue biopsy. Three patients also demonstrated extra-orbital involvement. Two patients (12.5%) had intraoperative steroid injection with curettage, and 1 patient (6.25%) underwent curettage only. The remainder of the patients (n = 13, 81.25%) received systemic steroids and chemotherapy after undergoing biopsy. All patients had complete remission of disease without any signs of recurrence, except for 1 case of refractory LCH.

Conclusions: LCH is a rare disorder of the orbit and should be considered in the differential diagnosis for osteolytic lesions involving the superior orbit among the pediatric age group. Histopathologic confirmation is mandatory. Although optimal treatment remains controversial, complete removal of unifocal orbital LCH is recommended and may be achieved through excision and curettage.