On day 14 of every treatment cycle you will return to the clinic to receive an infusion of Avastin. At that time, your blood pressure will be taken, and you will have a physical examination and an evaluation of your performance status. On day 21 of each cycle you will have blood work (1-2 tablespoons) to see how well you are tolerating the treatment. Every 8 weeks (after every 2 cycles immediately prior to your next cycle) you will have an MRI of your brain to determine measurements of your tumor.