Stem cell treatment During high-dose chemotherapy, the stem cells that were taken from your child and frozen during induction chemotherapy will be replaced in a stem cell transplant. This process aims to restore the blood-producing cells in the bone marrow using your child’s own cells, meaning that there is no risk of rejection as there could be with donor stem cells. The stem cells are thawed and given by a drip back into the body after any high-dose treatment has destroyed the cells in the body. Usually, within a couple of weeks, the stem cells will begin making new white blood cells. This is followed by new platelet production and new red blood cell production. Until this happens your child is at risk of infection and stays in a special hospital room in isolation. Once this is complete and dependant on the risk group, your child may undergo radiotherapy on the area around their primary tumour site. Again, this is to try to ensure any cancer cells left over from surgery are killed off.