Cauda equina paraganglioma.

Two paragangliomas resected from the cauda equina had similar morphology, both containing cells having dense core secretory granules with no associated sustentacular or supporting cells. The cells were arranged in characteristic lobules that were surrounded by basement membrane and separated by a fibrovascular stroma. This tumor, although rarely found elsewhere in the central nervous system, does occur in the region of the filum terminale, and causes a clinical syndrome typical of tumors in that area.