Juvenile xanthogranuloma with central nervous system involvement.

An 18-year-old man has been followed in our department since age 10 years when he began to develop numerous yellow, papular lesions on the scalp, face, neck, trunk, and upper extremities. The lesions enlarged slowly to form yellow-brown nodules measuring up to 6 cm. During this period five of the nodules and two small papules were excised. Histopathology was consistent with juvenile xanthogranuloma (JXG). Recently, the patient complained of significant loss of memory, and a computed tomography scan was performed showing several cerebral and cerebellar lesions. The cutaneous lesions in our patient were almost identical to those described elsewhere as being characteristic of progressive nodular histiocytoma. The many clinical and histopathologic similarities between lesions of progressive nodular histiocytoma and JXG suggest that they may represent a continuum rather than two distinct disease processes. Given the fact that there are no histopathologic differences with JXG, as well as the wide range of clinical lesions that JXG may adopt, there is no reason to separate the entities. Although JXG lesions are usually believed to be benign and self-healing, large nodular forms can be associated with visceral lesions. Only four previous cases of cutaneous JXG with central nervous system involvement were found in a review of the literature.