Chemotherapy as prophylaxis and treatment of meningosis in children less than 3 years of age with medulloblastoma.

The outcome of children less than 3 years of age with medulloblastoma has been poor in comparison to older children. The cure rates were below 30%, and the quality of life for cured children was frequently reduced by a complex syndrome of long-term sequelae including intellectual retardation and growth hormone deficiency. Due to the deleterious side-effects of radiotherapy in very young children chemotherapy has played an important role in this group of patients. Firstly, chemotherapy should improve their survival rate. Secondly, it should allow dose reduction of craniospinal irradiation and a smaller involved field. With the goal of improving quality of life radiotherapy should be delayed or even replaced by postoperative chemotherapy. The EFS of low-risk patients steadily improved and is now as high as at least 50%. Since most patients of this group do not need radiation, treatment-related long-term sequelae are minimal. High-risk patients, by contrast, with metastatic disease or measurable postoperative tumor still have a very disappointing progression-free survival in a range below 30% at 3 to 4 years in all large studies. Therefore prevention and effective therapy of meningosis, as well as a good response to induction chemotherapy, are essential for the outcome. Strategies to increase the efficacy of conventional treatment modalities in high-risk patients are under investigation. Recently, interesting results have been published on high-dose chemotherapy followed by autologous stem cell rescue and intraventricular administration of the alkylating agent mafosfamide.