Inclusion Criteria:

• Participants ≥ 18 years < 65 years of age.
• KPS ≥ 60.
• Negative pregnancy test done < 7 days prior to registration, for persons of childbearing potential only.
• Patients with a previous histological diagnosis of GBM that show recurrence at the same location, who are candidates to- and will undergo a redo craniotomy for excision of recurrent tumor.  
• Patients have undergone previous standard of care as outlined by Stupp et al. (2004) which include maximal safe resection followed by concomitant radiation therapy and chemotherapy with oral temozolomide.  
• There is measurable disease according to the iRANO criteria defined in section “11.2.1 Measurable Disease” of this protocol.  
• Adequate organ function as assessed by the following laboratory values ≤ 3 weeks prior to registration:
  • Serum creatinine and urea ≤ 2 times the upper limit of normal;
  • ALT, AST and alkaline phosphatase ≤ 3 times the upper limit of normal, and bilirubin ≤ 2.5 mg/dL;
  • Prothrombin time ≤1.5 times upper limit of normal;
  • INR and PTT ≤ 1.5 times the upper limit of normal;
  • Hemoglobin ≥ 9 g/dL;
  • Platelets ≥ 100 x 10^9/L;
  • Absolute Neutrophil Count (ANC) ≥ 1.5 x 10^9/L.
• Willing to return to enrolling institution for follow-up (during the Active Monitoring Phase of the study).
• Patient or Legally Authorized Representative (LAR) is able to fully understand and provide written and verbal consent for the protocol.
• Willingness to provide mandatory blood specimens for correlative research.
• Willingness to provide mandatory tissue specimens for correlative research.
• Willingness to undergo Ommaya reservoir placement and provide CSF samples for correlative research.

Exclusion Criteria:

• Patients who are undergoing biopsy only or non-eligible for a surgical intervention.
• Tumors located in the brain stem, midbrain, or thalamus.
• Previous treatment with Bevacizumab.
• Radiographic evidence of leptomeningeal disease.

Eligibility last updated 3/2/23. Questions regarding updates should be directed to the study team contact.