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Chemotherapy of pediatric posterior fossa tumors.

Results of chemotherapy of recurrent posterior fossa tumors in children are presented. Cerebellar astrocytoma, ependymoma, and brain stem glioma have all shown objectively determined responses to treatment with nitrosourea compounds (BCNU or CCNU). Medulloblastoma has shown objectively determined response to various chemotherapeutic agents; but in our experience the best responses have been obtained with a combination of a nitrosourea (CCNU), vincristine, and procarbazine. Although chemotherapy after recurrence has significantly prolonged the life of the patients, cure has not been achieved. Theoretical considerations regarding the failure of initial therapy and the inadequacy of subsequent chemotherapy are discussed.