Myeloablative chemotherapy with autologous bone marrow rescue in young children with recurrent malignant brain tumors

Purpose: This study evaluates the outcome of myeloablative chemotherapy and autologous bone marrow rescue (ABMR) with or without radiotherapy in children younger than 6 years of age with recurrent malignant brain tumors who had not previously been exposed to conventional fractionated external- beam irradiation. Patients and Methods: Patients underwent surgery and/or conventional chemotherapy at the time of recurrence to achieve minimal residual disease (two of these patients also underwent local single-fraction gamma-knife radiosurgery). Myeloablative chemotherapy was then administered with carboplatin, thiotepa, and etoposide (16 patients), thiotepa and etoposide (three patients), or thiotepa, etoposide, and carmustine (BCNU; one patient). Autologous bone marrow was re-infused 72 hours after chemotherapy. Twelve patients received external-beam irradiation after recovery from ABMR. Results: Twenty patients with recurrent brain tumors aged 0.7 to 5.9 years (median, 2.9 years) at ABMR were evaluated. Two patients died of toxicity related to myeloablative therapy. Eight patients died of progressive disease. Ten of 20 (50%) patients (primitive neuroectodermal tumor (PNET)/medulloblastoma, three patients; cerebral PNET, three patients; glioblastoma multiforme, two patients; anaplastic astrocytoma, one patient; pineal PNET, one patient) are alive and disease free at a median of 37.9 months (range, 9.7 to 98.2 months) from ABMR (3-year overall survival [OS] rate of 43% ± 13% and event-free survival [EFS] rate of 47% ± 14%]. Seven of these 10 patients also received irradiation post-ABMR. Conclusion: Myeloablative chemotherapy with ABMR followed by additional external-beam irradiation appears to be an effective retrieval therapy for some young children with recurrent malignant brain tumors.