Managing patients who suffer from both cancer and end-stage renal disease is challenging because there is a paucity of data, especially for children. There are no published reports of adjuvant chemotherapy for medulloblastoma being used in children on dialysis. In this article we describe the case of an Italian 5-year-old boy on hemodialysis for chronic renal failure who presented with a desmoplastic medulloblastoma with extensive nodularity and nuclear β-catenin expression. The patient was treated with craniospinal irradiation after complete surgical resection, followed by six cycles of cyclophosphamide and vincristine. Vincristine was administered at the usual dosage for children with normal kidney function, cyclophosphamide was delivered after dialysis and over the course of the following day, starting with 50% of the commonly used dosage. This is the first case report of chemotherapy given during hemodialysis in a child with medulloblastoma. This treatment proved easy to administer despite the child's kidney disease and it maintained disease remission with no additional toxicity.