Study of Letrozole in Recurrent Gliomas

Inclusion Criteria

• •1. Radiographically, histologically or cytologically confirmed recurrent brain high grade glioma with plan for resection or biopsy.
• •\- Inclusion #1 for Sub-study Only: Radiographically, histologically or cytologically confirmed recurrent brain high grade glioma.
• •2. Age \>18 years.
• •3. ECOG performance status 0 -2 (Karnofsky \>60%, see Appendix A).
• •4. CBC/differential obtained within 28 days prior to registration on study, with adequate bone marrow function defined as follows:
• •* Absolute neutrophil count (ANC) ≥ 1,000 cells/mm3;
• •* Platelets ≥ 100,000 cells/mm3;
• •* Hemoglobin ≥ 8.0 g/dl (Note: The use of transfusion or other intervention to achieve Hgb ≥ 8.0 g/dl is acceptable).
• •5. Adequate hepatic function, defined as follows:
• •* Total bilirubin \< 2 x institutional ULN within 14 days prior to registration;
• •* AST or ALT \< 3 x institutional ULN within 14 days prior to registration.
• •6. Adequate renal function, defined as GFR \> 30 ml/min or Cr \< 1.5.
• •7. Negative serum pregnancy test within 2 weeks prior to registration for women of childbearing potential.
• •8. Imaging prior to treatment including MRI of brain (with contrast preferred but not required).
• •9. Ability to understand and the willingness to sign a written informed consent document.
• •10. Inclusion #10 for Sub-study Only: Measurable disease per RANO criteria within 28 days of starting treatment on this study.