Metastasizing ependymoma of the cauda equina.

A case of metastasizing ependymoma is described, only the second in the British literature. The tumour, which arose in the cauda equina, spread to humerus and pleura over a period of 32 years. It is postulated that, in common with most of the previously reported cases, dissemination was a direct consequence of either surgical intervention or radiotherapy since neither the primary tumour nor its metastases shows any of the conventional morphological criteria of malignancy. The literature of similar cases is briefly reviewed.