avastin for astrocytoma brain tumor

my wife is now 31 years old,she was diagnosed for brain tumor in 2002 after she had a  sudden sezuire, the ct show brain tumor ,the mri showed a 4 cm 5 cm 6 cm tumor in size.she had awake craniatomy in june 2002 for resection of brain tumor in the fronto temporal lobe ,the frozen section shows high grade tumor while the pathology then was low grade astrocytoma. she had full raido therapy treatment (30 sessions) in 2002 after one month of surgery .she was on tegretol only for sezuire control .till then everything was ok but in 2007 the seziure striked more ,the mri showed an increase in the size of the tumor cos it was not resected all due to place near motor and speach center. in 2008 she had another craniatomy for debulking of the tumor and the pathology showed still low grade (grade 2).but still seziure not controlled so the plane was to contol seziure by tegretol cr 400 mg bid and keppra 500 mg bid.and as we were advised to see an oncologyst ,the neuro oncologyst gave her temodal tablets 100 mg 20 tablets every month for one year,afetr one year or treatment theh tumor still enhancing so the place is for treatment with avastin ,what to do ,any advice? what do we expect as for prognosis? thank you all .