Medulloblastoma (MB) is the most common malignant brain tumour of childhood affecting around 100 children each year in the UK. It is one of the largest contributors to cancer deaths in children with survivors often suffering therapy related long term health problems. Approx 40% of patients treated for MB the condition will recur. Presently, the majority of patients with relapsed MB will die from their disease, as most existing treatments for relapsed MB can only prolong life and are not a cure

The purpose of this study is to identify genetic patterns that detect those children who are more likely to suffer from relapsed MB. This will enable their treatment to be intensified as soon as the disease is diagnosed, in the hope of preventing relapse.