Tandem high-dose chemotherapy and autologous stem cell rescue in children with newly diagnosed high-risk medulloblastoma or supratentorial primitive neuro-ectodermic tumors

Background: To assess the feasibility and effectiveness of high-dose chemotherapy (HDC) with stem cell support followed by conventional craniospinal radiotherapy (RT) as treatment for children older than 5 years of age with newly diagnosed high-risk medulloblastoma (MB) or supratentorial PNET (sPNET). Procedure: Between May 2001 and April 2010, 24 children older than 5 years of age (MB=21; sPNET=3), fulfilling inclusion criteria at diagnosis, were treated at Gustave Roussy. After conventional chemotherapy, they received two courses of high-dose thiotepa (600mg/m²) followed by craniospinal RT. Results: The median follow-up was 4.4 years (range, 0.8-11.3 years). For children with metastatic MB, the 5-year event-free survival (EFS) and overall survival (OS) were 72% and 83%, respectively. The toxicity was manageable. No toxic death occurred. At the most recent evaluation, among the 24 children who had at least one Full Scale Intellectual Quotient (FSIQ) examination at a median follow-up of 3.79 years after diagnosis, the mean estimated FSIQ was 82 (range, 56-114). Conclusions: In children with metastatic MB, tandem HDCT with ASCT followed by conventional craniospinal RT proved its feasibility without jeopardizing survival.