Inclusion Criteria:

- Patients with histologically proven intracranial glioblastoma multiforme (GBM) and
gliosarcoma (GS) will be eligible for this protocol.

- Diagnosis will have been established by biopsy or resection no more than 5 weeks
prior to treatment.

- An magnetic resonance imaging (MRI) or computer tomography (CT) must be obtained
within 14 days of treatment. The use of MRI rather than CT is preferred. The same
type of scan, i.e., MRI or CT must be used throughout the period of protocol
treatment for assessment of tumor status.

- Patients without measurable or assessable disease are eligible.

- Patient must not have had prior cranial radiation therapy.

- Patients must not have received prior cytotoxic drug therapy, non-cytotoxic drug
therapy, or experimental drug therapy for brain tumors.

- Patients who received Gliadel wafers at the time of original resection will be
excluded.

- Patients must have a plan to begin partial brain radiotherapy the same day as Tarceva
and temozolomide.

- Radiotherapy must be a) at the Radiation Oncology Department of the University of
California San Francisco or b) at an affiliated site such that a radiation oncologist
at UCSF can provide assurance that radiation can be performed as specified.

- Radiotherapy must be given by external beam to a partial brain field in daily
fractions of 1.8 to 2.0 Gy, to a planned total dose to the tumor of 5940-6100 cGy.

- Stereotactic radiosurgery and brachytherapy will not be allowed.

- Patients must be willing to forego other cytotoxic and non-cytotoxic drug therapy
against the tumor while being treated with Tarceva and temozolomide.

- All patients must sign an informed consent indicating that they are aware of the
investigational nature of this study.

- Patients must be registered in the UCSF Neuro-Oncology database prior to treatment
with study drug.

- Patients must sign an authorization for the release of their protected health
information.

- Patients must be 18 years or older, and with a life expectancy > 12 weeks.

- Patients must have a Karnofsky performance status of > 60.

- Patients must have adequate bone marrow function (WBC > 3,000/µl, ANC > 1,500/mm^3,
platelet count of > 100,000/mm^3, and hemoglobin > 10 gm/dl), adequate liver function
(SGOT, and bilirubin < 2 times ULN), and adequate renal function (creatinine < 1.5
mg/dL or calculated creatinine clearance > 60 cc/min) before starting therapy. These
tests must be performed within 14 days prior to registration. Eligibility level for
hemoglobin may be reached by transfusion.

- Patients must not have any significant medical illnesses that in the investigator's
opinion cannot be adequately controlled with appropriate therapy or would compromise
the patient's ability to tolerate this therapy.

- Patients with a history of any other cancer (except non-melanoma skin cancer or
carcinoma in-situ of the cervix), unless in complete remission and off of all therapy
for that disease for a minimum of 3 years are ineligible.

- This study was designed to include women and minorities, but was not designed to
measure differences of intervention effects. Males and females will be recruited
with no preference to gender. No exclusion to this study will be based on race.

- Patients must not have active infection.

- Patients must not be pregnant/breast feeding and must agree to practice adequate
contraception.

- Women of childbearing potential must have a negative B-HCG pregnancy test documented
within 7 days prior to registration.

- Patients must not be pregnant because of the uncertainty that study drug may be
potentially embryotoxic. For this reason, women of child-bearing potential and men
must agree to use adequate contraception (hormonal or barrier method of birth
control) prior to study entry, for the duration of study participation, and continue
approximately 12 weeks after the study is completed. Should a woman become pregnant
or suspect she is pregnant while participating in this study, she should inform her
treating physician immediately.

- Patients must not have any disease that will obscure toxicity or dangerously alter
drug metabolism.

- Patients must not have serious inter-current medical illness.

- Patient with recent thromboembolic disease (deep vein thrombosis and pulmonary
embolism) are eligible if they are clinically stable and the thromboembolic event
occurred more than 3 weeks prior to enrollment into this protocol.

Exclusion Criteria:

- Patients who do not meet one or more of the inclusion criteria above.