The purpose of this study is to find the highest safe dose of a new medicine, a radioactive antibody called 131I-8H9, in children and adults with cancer of the brain or brain covering (leptomeninges) that has returned after standard treatment or for which no standard therapy exists.
Antibodies are made by the body to fight infections, and in some cases, to fight tumors. The antibody 8H9 is made by mice and can attack many kinds of tumors. The medicine being evaluated in this study consists of 8H9 attached to radioactive iodine (131I). This drug has been given by vein to patients to see if it can find cancer cells. This is the first study assessing 131I-8H9 given into the spinal fluid (“intrathecally”) to kill cancer cells.