Between April 1986 and March 1989, ten patients under 21 years of age with histologically confirmed malignant astrocytoma, received marrow-ablative chemotherapy with either thiotepa and Etoposide (five patients) or thiotepa, Etoposide and BCNU (five patients), followed by bone marrow 'rescue'. Nine patients had glioblastoma multiforme (GBM), and one patient had an intrinsic brain stem anaplastic astrocytoma (AA). Seven patients were treated for recurrent tumor. Two patients who developed GBM as second malignancies were treated directly following surgical resection. One patient had received irradiation only for recently diagnosed cervical spinal cord GBM. Thiotepa was administered at a total dose of 600-900 mg/M2 over three days, Etoposide was administered at a total dose of 1500 mg/M2 over three days, and BCNU was administered at a total dose of 600 mg/M2 over four days. Non-hematopoietic toxicities have been mainly transient, predictable and acceptable, consisting of oropharyngeal mucositis, cutaneous hyperpigmentation, erythema and desquamation. Four patients achieved complete responses (CR), as determined by radiographic evaluation (CT and/or MRI) on day 28 post-marrow infusion. The mean remission duration of those with CR is 290+ days; two patients presently remain in remission. Two patients achieved partial responses (PR, greater than 50% tumor shrinkage) by day 28 post-marrow infusion; both developed disease progression, at day 61 and 94 post-marrow infusion, respectively. One patient, with a brain stem AA, had stable disease maintained for 13 months post-marrow infusion. With a total (CR + PR) response rate of 60%, these regimens merit evaluation in broader categories of recurrent brain tumor patients, as well as in patients with newly-diagnosed GBM.