Purpose: In a previous randomized trial, the addition of adjuvant chemotherapy to postoperative radiotherapy proved beneficial in the treatment of childhood high-grade astrocytomas. The present study tests the hypothesis that an eight-drug adjuvant chemotherapy regimen would improve survival in such children compared with the three-drug regimen of the prior study.
Patients and methods: Between April 1985 and May 1990, patients between the ages of 18 months and 21 years with newly diagnosed high-grade astrocytomas were eligible for this study, as determined by the treating institution's histopathologic diagnosis. Treatment consisted of postoperative local-field radiotherapy and adjuvant chemotherapy, either lomustine (CCNU), vincristine, and prednisone (control regimen) or eight-drugs-in-1-day chemotherapy (experimental regimen). Two cycles of postoperative preirradiation chemotherapy were administered in the experimental regimen. Patients were evaluated radiographically every 3 months after irradiation.
Results: Eighty-five eligible patients were randomized to the control regimen and 87 to the experimental regimen. The progression-free survival (PFS) and overall survival (OS) at 5 years were 33% (SE = 5%) and 36% (SE = 6%), respectively. There was no statistical difference in outcome between the two chemotherapy regimens. In patients with confirmed diagnoses of anaplastic astrocytoma (AA) or glioblastoma multiforme (GBM), anaplastic astrocytoma, greater than 90% resection, and nonmidline tumor location were characteristics predictive of an improved PFS. There was a difference in toxicity between the two chemotherapeutic regimens, with greater myelosuppression and hearing loss in the experimental regimen. Tumor recurrence occurred primarily within the primary tumor site.
Conclusions: There is no benefit to the treatment of high-grade astrocytomas in children with eight-drugs-in-1-day chemotherapy compared with CCNU, vincristine, and prednisone. Extent of tumor resection and histopathologic diagnosis are significant prognostic variables. The overall outcome for children with high-grade astrocytomas remains poor.