Table 1. Patient demographics and histological diagnosis.

Diagnoses were made according to the WHO, on the basis of the consensus of pathologists and international experts, providing definition for brain tumors in cancer research (47). For the “Other” classification, only normal brain samples were used from the indicated patients; no samples with cancer cells present were acquired.

n patientsn samples
Age (years), median (range)53 (30–89)
WHO gradeGrade 2435
  Astrocytoma326
  Oligodendroglioma19
Grade 3329
  Astrocytoma110
  Oligodendroglioma110
  Oligoastrocytoma19
Grade 4 (GBM)868
Other: metastatic229
Tissue typeNormal brain66
Dense cancer39
Invasive cancer cells56
Total17161