Intraspinal primitive neuroectodermal tumour: report of two cases and review of the literature.

Two patients with primary intraspinal primitive neuroectodermal tumour are presented. In a 32-year-old man, the tumour evolved intradurally from a sacral nerve root. Despite repeated surgery and radiochemotherapy, the patient suffered multiple intraspinal tumour relapses and intracranial seedings, and died 29 months after the first diagnosis. In a 17-year-old male adolescent, the tumour was located in the lumbar epidural space, extending into the paraspinal muscles. Following resection and radiochemotherapy, the patient is free from disease 23 months after the initial presentation. The clinical, radiological, histopathological and cytogenetic findings of both patients are presented and the relevant literature is reviewed. Particular attention is given to the histogenetic relationship between peripheral primitive neuroectodermal tumour and Ewing's sarcoma.