Grade 4 Glioma Anaplastic Astropsytoma - 1259255

My brother has Grade 4 Glioma Anaplastic Astropsytoma. He was on tremador and did 11 days of radiation before stopping treatment at the end of August. Hospice has been called in and we are taking things day by day. He has 2 tumors that have grown together and have spidered out on the right side of his brain. My guess would be that it is as big as an average size hand. This MRI was taken in early August during hospitalization. Seizures have started again and another seizure med is being given every 12 hours in conjunction with dilantin to help. He is partially paralyzed on his left side and is having problems with getting his words out right. He also does not sleep much due to the steroids given every 6 hours. He is in good spirits, can walk with a walker, he is eating, and using the bathroom. Last seizure lasted 5-10 minutes and he hasn't had one in almost a day now. My qusetion is what is the average life expectancy for my brother at this stage with the symptoms he is having?