Paraganglioma of the cauda equina.

Paraganglioma rarely occurs in the spinal canal. Paraganglioma of the cauda equina has been reported in only 25 cases in the world literature since first reported by Lerman, et al., in 1972. In 1970, Miller reviewed the first case of these, but he confused it with secretory ependymoma. The characteristic histologic appearance is of a Zellballen pattern that consists of polygonal cells separated by a delicate fibrovascular stroma. However, a diagnosis is accurately confirmed only by electron microscopic examination. We present a confirmed case of paraganglioma of the cauda equina in a 49-year-old woman who was treated operatively, that is unusual in the presented enormity of the tumor, and review the previously reported cases.