Primary Langerhans' cell histiocytosis of the central nervous system with fatal outcome. Case report.

An unusual case of primary parenchymal Langerhans' cell histiocytosis of the central nervous system is reported. The definitive diagnosis was obtained by ultrastructural detection of Birbeck granules and by immunohistochemical evidence of CD1a expression. Despite complete surgical resection, there was an early recurrence with multiple central nervous system metastases leading to a fatal outcome.