Inclusion Criteria:

- Age: 18 years or older

- Histological confirmation of supratentorial GBM

- KPS > 60

- Neurological function 0 or 1

- Adequate bone marrow as defined below:

- absolute neutrophil count (ANC) > 1500 cells/mm3

- platelets > 100,000 cells/mm3

- hemoglobin > 10g/dl

- Adequate renal function as defined below:

- BUN < 25mg/dl within 14 days prior to study registration

- creatinine of 63 to 103 umol/L within 14 days prior to study registration

- Adequate hepatic function as defined below:

- Bilirubin of 3 to 21 umol/L within 14 days prior to study registration

- ALT & AST < 3xnormal range within 14 days prior to study registration

- Neoadjuvant TMZ to start within 3 weeks of surgery/biopsy if no resection was deemed
feasible

- A diagnostic contrast-enhanced MRI or CT scan of the brain must be performed
preoperatively and postoperatively.

- History, physical and neurological examination within 14 days prior to study
registration.

- For females of child-bearing potential, negative pregnancy test within 72 hours prior
to starting TMZ.

- Able to sign an informed study-specific consent

Exclusion Criteria:

- Margin of contrast-enhanced residual mass closer than 15mm from the optic chiasm or
optic nerves.

- Prior invasive malignancy, unless disease-free for >3years

- Recurrent or multifocal GBM

- Severe co-morbidities such as

- unstable angina

- transmural myocardial infarction within 6 months

- COPD at the time of registration

- Hepatic insufficiency

- Bacterial or fungal infection requiring IV antibiotics at the time of registration

- Acquired Immune Deficiency Syndrome (AIDS)

- Major medical illnesses or psychiatric impairments

- Pregnant women or lactating women