Combined modality therapy for poorly differentiated gliomas of the posterior fossa in children: a Children's Cancer Group report

To study the effectiveness of combined chemotherapy and radiotherapy for children with high-grade astrocytomas of the posterior fossa.In the CCG-945 study, 250 patients were treated by members of the Children's Cancer Group (CCG). Sixteen children were randomly assigned to one of two chemotherapy regimens, vincristine, lomustine, and prednisone or '8-in-1', using the same involved-field irradiation in both. Six infants received 8-in-1 chemotherapy before involved-field irradiation. All pathologic specimens had central review.Twenty-two patients with an institutional diagnosis high-grade posterior fossa tumors received chemotherapy and/or irradiation. Fifteen were confirmed by central review to have high-grade gliomas. Overall survival for confirmed high-grade astrocytoma of the posterior fossa was approximately 36 +/- 13% at 5 years for the children (n = 11) and 25 +/- 15% at 5 years for the infants (n = 4).Involved-field irradiation with chemotherapy appeared to prevent extraneural and subarachnoid metastases. We also confirmed the rarity of the tumor (6% of patients registered). Further Phase III trials are necessary to improve survival in this aggressive tumor.