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Benign ependymomas of the posterior fossa in childhood.

A series of 22 infants and children with posterior fossa benign ependymomas treated surgically during the past 12 years is presented. All patients were operated on with posterior fossa craniotomy: visible total resection in 10, subtotal resection in 9, partial resection in 2 and biopsy only in 1. One patient (4.5%) died shortly after surgery. Only 5 patients had documented infiltration of the floor of the fourth ventricle. Postoperative radiotherapy was administered with variable radiation fields and doses. Two out of six patients who had total resection and postoperative radiation therapy did not show recurrence during at least 26 months follow-up period. However, patients with incomplete tumor resection almost invariably developed recurrence. An attempt should be made to remove posterior fossa ependymomas totally at the initial craniotomy. The risk periods for recurrence were between 1 and 2 years after subtotal resection and between 2 and 3 years after total resection. In our experience, gross recurrent tumors appear to be resistant to chemotherapy, and a combination of surgery and radiation therapy does not necessarily prevent recurrence. Newer agents or protocols of adjuvant chemotherapy are needed to explore.