Inclusion Criteria:

- 18 years of age or older.

- Documented histologic diagnosis of relapsed or refractory glioblastoma multiforme
(GBM), anaplastic astrocytoma (AA) or anaplastic mixed oligoastrocytoma (AOA).

- Circumscribed tumor recurrence with less than 3.5 cm greatest diameter

- Patients with histologically confirmed low-grade brain tumor relapse with an
enhancing tumor on MRI will be evaluated for toxicity only.

- Patients must have at least one confirmed and evaluable tumor site.

- Patients must have a Karnofsky performance status 70% (or the equivalent ECOG level
of 0-2)

- Patients must agree to use a medically effective method of contraception during and
for a period of three months after the treatment period.

Exclusion Criteria:

- Women who are pregnant or lactating.

- Patients with significant intercurrent medical or psychiatric conditions that would
place them at increased risk or affect their ability to receive or comply with
treatment or post-treatment clinical monitoring.

- Low GFR or history of hepatorenal syndrome