Have you asked your Dr. about meds to help their appetite? My 15 yr. old daughter was dx with a brain tumor called choroid plexus carcinoma in January 2002 so it's been almost a year & between chemo and radiation she couldn't eat. It's not the same kind of brain tumor you're dealing with but her Dr. put her on a drug called megestrol, it does seem to help her, along with zofran for nausea. There is another drug to help with appetite called marinol (excuse spelling) if the megestrol doesn't help. Good luck.