Dietary Methionine Restriction Plus Temozolomide for Recurrent GBM

Inclusion Criteria:

1. Histologically proven glioblastoma multiforme (GBM).
2. Unequivocal evidence of tumor recurrence or progression by MRI (or CT brain if a patient can not undergo MRI). Radiotherapy (with or without radiosensitizing drugs) must have been completed in the past. The earliest a patient can be enrolled in this study after radiotherapy is 14 days. The scan done prior to study entry documenting progression will be reviewed by the primary investigator to document tumor volume changes to provide a gross assessment of growth rate.
3. Patients may have had: a) no prior chemotherapy, b) 1 prior adjuvant chemotherapy, c) 1 prior adjuvant chemotherapy followed by 1 regimen for recurrent disease, or d) 1 or 2 prior chemotherapy regimens for recurrent or progressive tumor.
4. All patients must sign an informed consent indicating that they are aware of the investigational nature of this study in keeping with the policies of this hospital.
5. Enrollment MRI or CT scan of the brain must be performed within 14 days of registration. Patients having undergone recent resection of recurrent or progressive tumor will be eligible for assessment of response as long as there is residual enhancing evaluable disease that is documented by appropriate neuroimaging and patients have recovered from the effects of surgery. Patients who after surgery have no residual enhancing disease will still be eligible for enrollment, but only assessable for time to progression, and not for response.
6. Patients must have a life expectancy \> 8 weeks.
7. Patients must have a Karnofsky performance status of \> or = 60 (Karnofsky Performance Scale).
8. Patients must have recovered from the toxic effects of prior therapy and/or at least 2 weeks from vincristine, 6 weeks from nitrosoureas, and 3 weeks from procarbazine administration. Patients must have recovered from the toxic effects of any other cytotoxic drugs which they may have received and must be 1 week from the completion of any non-cytotoxic drug therapy (e.g. 13-cis-retinoic acid, thalidomide, tamoxifen, etc.). For those patients previously treated with temozolomide, they may enroll and start the diet even 1 day after their last temozolomide dose.
9. Patients must have adequate bone marrow function (ANC\> or = 1,500/mm3 and platelet count of \> or = 100,000/mm3), adequate liver function (SGPT and alkaline phosphatase = or \<2 times normal, bilirubin = or \<1.5 mg%), and adequate renal function (BUN or creatinine = or \<1.5 times institutional normal) prior to starting therapy.
10. All acute toxic effects (excluding neurotoxicity or alopecia) of any prior therapy must have resolved to Common Toxicity Criteria (CTC) grade = or \< 1.
11. Patients who are eligible for the trial and who require resection of their tumor may begin the dietary restriction component of the therapy prior to their surgery providing the time to surgery is greater than 6 days. In these patients, tissue collected at surgery will be analysed for the effects of treatment. After surgery, patients will resume an ad lib diet for anywhere from 5-14 days prior to the re-initiation of the dietary methionine restriction at the same dose level and continuance with the trial.

Exclusion Criteria:

1. 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.
2. Patients have one or more of the following conditions may not participate in this study: a) active infection; b) pregnancy and/or disagree to practice adequate contraception; c) disease that will obscure toxicity or dangerously alter drug metabolism; d) serious intercurrent medical illness.