Langerhans cell histiocytosis of the medial canthus. A presentation of a rare disease in uncommon localization

Abstract

Introduction: Langerhans cell histiocytosis (LCH, also known as histiocytosis X) is a rare disease involving clonal proliferation of Langerhans cells usually presenting in childhood and adolescence. Its manifestations ranges from isolated bone and skin lesions to multisystem disease. The clinical course can appear self-limiting as well as in a fulminant and lethal form. Unifocal LCH of the periorbital bone and soft tissue is rare. Treatment is guided by extent of the disease and ranges from surgical excision to chemotherapy. Case report: A 31-year-old Caucasian man presented to us with a short-term history of indolent swelling of his right medial canthus. Magnetic resoncance imaging showed a subcutaneous lesion with contrast agent uptake and local bone thickness reduction at the right base of the nose. Excision biopsy and histomorphological evaluation showed evidence for LCH. Subsequent staging could objectify unifocal manifestation and continuous follow-up was initiated. Discussion: Unifocal LCH of the periorbital bone and soft tissue is rare and normally appears in childhood and adolescence. The actual literature shows usually an affection of the upper- or lower eye lid or the lateral canthus. Affection of the medial canthus in the presented case is unusual, particularly in a young adult. Conclusion: Suspicious orbital space-consuming lesions should be further evaluated by biopsy. Here – also in young adults – LCH should be taken into consideration as a possible differential diagnosis.