Memantine Hydrochloride and Whole-Brain Radiotherapy With or Without Hippocampal Avoidance in Reducing Neurocognitive Decline in Patients With Brain Metastases

This randomized phase III trial compares memantine hydrochloride and whole-brain radiotherapy with or without hippocampal avoidance in reducing neurocognitive decline in patients with cancer that has spread from the primary site (place where it started) to the brain. Whole brain radiotherapy (WBRT) is the most common treatment for brain metastasis. Unfortunately, the majority of patients with brain metastases experience cognitive (such as learning and memory) deterioration after WBRT. Memantine hydrochloride may enhance cognitive function by binding to and inhibiting channels of receptors located in the central nervous system. Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Using radiation techniques, such as intensity modulated radiotherapy to avoid the hippocampal region during WBRT, may reduce the radiation dose to the hippocampus and help limit the radiation-induced cognitive decline. It is not yet known whether giving memantine hydrochloride and WBRT with or without hippocampal avoidance works better in reducing neurocognitive decline in patients with brain metastases.