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Head and Neck Langerhans Cell Histiocytosis

Among the potential sites of involvement by Langerhans cell histiocytosis (LCH), the head and neck region is the most commonly cited. Though principally a pediatric disease, LCH can affect any age group. It can be unifocal (skeletal) or multifocal (skeletal and/or visceral); it appears as though the presence of visceral lesions is more common in the youngest patients, and may be associated in some with a rapidly progressive course resulting in death. Head and neck manifestations may mimic such varied entities as eczema, otitis media, osteomyelitis, and cholesteatoma. Current approaches to therapy are less aggressive than they were in the past, and are particularly intended to monitor for and treat any complicating secondary infections (which may develop in the youngest patients with multifocal disease including visceral involvement). The prognosis is very good for unifocal skeletal system disease, and poor for multifocal disease with involvement of tissues other than bone.