Carboplatin, Melphalan, Etoposide Phosphate, Mannitol, and Sodium Thiosulfate in Treating Patients With Previously Treated Brain Tumors

This phase I/II trial studies the side effects and best dose of melphalan when given together with carboplatin, etoposide phosphate, mannitol, and sodium thiosulfate and to see how well they work in treating patients with previously treated brain tumors. Drugs used in chemotherapy, such as melphalan, carboplatin, and etoposide phosphate, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing, or by stopping them from spreading. Osmotic blood-brain barrier disruption (BBBD) uses mannitol to open the blood vessels around the brain and allow cancer-killing substances to be carried directly to the brain. Sodium thiosulfate may help lessen or prevent hearing loss and toxicities in patients undergoing chemotherapy with carboplatin and BBBD. Giving carboplatin, melphalan, etoposide phosphate, mannitol, and sodium thiosulfate together may be an effective treatment for brain tumors.