Cohort 1 inclusion Criteria:
1. Between 01-01-2021 and 06-30-2025, an ICD-10-CM code C71.X (malignant brain neoplasm) and/or SNOMED CT 276826005 (malignant glioma of brain)
2. Between 01-01-2021 and 06-30-2025, current procedural terminology (CPT) codes indicating surgery with either a biopsy or excision of a brain tumor
3. Patients must be adults at least 18 years of age at time of surgery
4. CPT codes indicating submission of surgical sample for pathology for IDH testing
5. SNOMED CT codes for "glioblastoma" after IDH testing
6. Note that while a diagnosis can be made based on IDH from a biopsy or resection sample, resection is required for study inclusion.
7. A post-resection CPT code for brain MRI
8. At least one visit meeting all eligibility criteria between 15- and 50-days post-resection.
Cohort 1 exclusion Criteria:
1. History of malignant neoplasm of the brain \>12 months before index
2. Patients with prior chemotherapy, radiotherapy, immunotherapy or targeted treatment agents (including anti-angiogenic drugs) less than 12 months before and/or 14 days after resection.
Cohort 2 inclusion Criteria:
Patients must meet all eligibility criteria for Cohort 1 and the following:
1. Brain MRI scan post-resection available for evaluation
2. Karnofsky performance score of at least 60
3. Laboratory values within the following specified ranges:
1. Absolute neutrophil count of at least 1.5 k/microliter (μL)
2. Platelet count of at least 100 k/μL
3. Hemoglobin level of at least 9 gram/deciliter (dL)
4. Serum creatinine level of at most 1.8 milligram(mg)/dL or creatinine clearance of more than 50 milliliter/min
5. Bilirubin level of at least 1.5 mg/dL
6. ALT level of at most 3.0 × upper limit of normal (ULN)
7. AST of at most 3.0 × ULN
8. PT of at most 1.5 × ULN
9. INR of at most 1.5 × ULN
10. PTT of at most 1.5 × ULN
Cohort 2 exclusion Criteria:
1. No resection was performed
2. One-year pre-index history of spontaneous or tumor-related intracranial hemorrhage
3. One-year pre-index history of diffuse leptomeningeal disease
4. Patients on dexamethasone daily dosing more than 2 mg at index
5. Three-month pre-index history of cardiovascular disease (myocardial infarction, coronary artery disease, arrhythmia, unstable angina pectoris, cerebrovascular accident)
6. Six-month pre-index history of acquired coagulopathies (hemorrhagic disorder due to circulating anticoagulants or acquired coagulation factor deficiency)
7. Six-month pre-index history of clinically significant bleeding
8. Known predisposition for bleeding such as von Willebrand's disease or other such condition(s) (i.e., hereditary deficiency of factor VIII, IX and XI)
9. Six-month pre-index history of significant psychiatric illness
10. Six-month pre-index history of major infection
11. Prior malignancy except for non-melanoma skin cancer and carcinoma in situ of the cervix or bladder
12. Receiving any of the following medications at the index date:
1. Any anticoagulant, including low-molecular weight heparin and warfarin within two months pre-index
2. Any digitalis alkaloid (digoxin, digitoxin, lanatoside C) within two months pre-index
3. Antiangiogenic drugs (e.g., bevacizumab) two weeks before or two weeks after index
4. Theophylline two weeks before or two weeks after index
13. Patients with a record of pregnancy, pregnancy termination, or hospital admissions for birth/delivery, or a positive laboratory test indicating pregnancy up to 9 months before index date
14. Known to be positive for the human immunodeficiency virus
15. Patients not receiving radiation therapy in the year after diagnosis.
