Inclusion Criteria:

- Patients must have EITHER

- Histologically confirmed intracranial malignant glioma of the following types:
Glioblastoma, Anaplastic astrocytoma (AA), Anaplastic oligodendroglioma (AO),
Anaplastic oligo-astrocytoma (AOA) also called anaplastic mixed gliomas, Malignant
glioma NOS (not otherwise specified). Patients will be eligible if the original
histology was low-grade glioma and a subsequent histological diagnosis of a high
grade (malignant) glioma is made.

OR

- Histologically confirmed low grade (WHO grade II) gliomas (such as low grade
astrocytoma, low grade oligodendroglioma, low grade oligo-astrocytoma (mixed
gliomas), or low grade glioma NOS) IF there is radiographic evidence by MRI of
malignant transformation but histologic confirmation of high grade (malignant)
transformation would not be otherwise undertaken for routine clinical care. Inclusion
of patients in this group will allow increased accrual rapidity by enrolling patients
who are otherwise ineligible for almost all malignant glioma trials yet whom are
treated presumptively for malignant glioma. The primary aim of the phase I study is
not determination of efficacy. Therefore, inclusion of such patients will not affect
efficacy analyses.

Participating site confirmation is adequate.

- Able to undergo brain MRI scans.

- MRI scan with gadolinium contrast showing geographically-circumscribed tumor ≤40 cc
incorporating both enhancing and non-enhancing volume. This is calculated by the
product of maximum measurements in 3 dimensions divided by 2. Any questions should
be addressed to the PIs or co-PIs. (Scan must be performed on a steroid dosage that
has been stable or decreasing for at least 5 days. Patients on no steroids are
eligible. If the steroid dose is increased between date of imaging and registration,
a new baseline MRI is required).

- Prior treatment with approximately 60 Gy of radiotherapy.

- Patients must have recovered from the toxic effects of prior therapy including but
not limited to:

An interval of ≥ 4 weeks (28 days) from prior cytotoxic therapy except 6 weeks from
nitrosoureas An interval of ≥ 1 week (7 days) from any non-cytotoxic agents An interval of
≥ 3 months from the completion of radiation therapy

- Absolute neutrophil count ≥ 1,500/mm3.

- Platelet count ≥ 100,000/mm3.

- Hemoglobin ≥ 10 g/dl.

- Serum creatinine ≤ 2 times upper limit of normal.

- Total bilirubin ≤ 2 times upper limit of normal.

- SGOT and SGPT both ≤ 3 times upper limit of normal.

- ≥18 years of age.

- Karnofsky Performance Score ≥ 60

- Life expectancy ≥ 12 weeks

- Men and women with reproductive potential must agree to use an acceptable method of
birth control during treatment and for six months after completion of treatment.

- Written informed consent prior to registration on study.

Exclusion Criteria:

- Prior treatment with radiosurgery

- Prior disease progression/recurrence during or immediately following treatment with
bevacizumab. Any question should be directed to the PI.

- Multicentric glioma

- Other malignancy (with the exception of cervical carcinoma in situ or basal cell
carcinoma of the skin) for which there has been treatment within the last 3 years

- Serious medical or psychiatric illness that would in the opinion of the investigator
interfere with the prescribed treatment.

- Pregnant or breast feeding women

- Inadequately controlled hypertension (defined as systolic blood pressure >150 mmHg
and/or diastolic blood pressure > 100 mmHg)

- Any prior history of hypertensive crisis or hypertensive encephalopathy

- Unstable angina within 12 months of study enrollment

- Grade 2 or greater congestive heart failure

- History of myocardial infarction, unstable angina, stroke, or transient ischemic
attack within 12 months prior to Day 1

- Significant vascular disease (e.g., aortic aneurysm, requiring surgical repair or
recent peripheral arterial thrombosis) within 6 months prior to Day 1

- History of hemoptysis ≥1/2 teaspoon of bright red blood per episode) within 1 month
prior to Day 1

- Evidence of bleeding diathesis or significant coagulopathy (in the absence of
therapeutic anticoagulation)

- Major surgical procedure, open biopsy, or significant traumatic injury within 28 days
prior to Day 1 of treatment or anticipation of need for major surgical procedure
during the course of the study

- Core biopsy or other minor surgical procedure, excluding placement of a vascular
access device, within 7 days prior to Day 1

- Serious, non-healing wound, active ulcer, or untreated bone fracture

- Proteinuria as demonstrated by a UPC ratio ≥ 1.0 at screening

- Known hypersensitivity to any component of bevacizumab

- History of peptic ulcer within the last 6 months

- Clinically significant peripheral vascular disease

- Craniotomy wound that has not sufficiently healed

- History of abdominal fistula, gastrointestinal perforation, or intra-abdominal
abscess within 6 months prior to study enrollment

- Glioma showing prior spontaneous hemorrhage as determined from the clinical history
or from any preoperative CT or MRI scan (excluding grade 1 punctate, incidentally
found).

- Longest uni-dimensional measurement of contrast enhancing tumor ≥ 4cm. Tumors
exceeding this limit may be eligible and any question should be directed to a
Radiation Oncology Investigator and the PI.

- Tumor must not invade the corpus callosum

- Tumor must not invade the brainstem

- Suspected or documented radionecrosis