Coexistent intra- and extracranial mass lesions: an unusual manifestations of histiocytosis X.

Eosinophilic granuloma, Hand-Schuller-Christian disease, and Letterer-Siwe disease are three disorders characterized by proliferating histiocytes. Collectively, they are called histiocytosis X. Histiocytosis X often presents with lytic calvarial lesions [1]. Hypothalamic involvement is the most common intracranial manifestation [2]. Solitary histiocytosis X within the cerebral hemispheres, although rare, has been reported [3, 4]. We present a case of solitary eosinophilic granuloma of the temporal lobe with coexistent involvement of the dura, calvaria, and temporalis muscle.