More recent studies suggest that astrocytes, oligodendrocyte progenitor cells, and neural stem cells could all serve as the cell of origin.Glioblastomas are characterized by the presence of small areas of necrotizing tissue that are surrounded by anaplastic cells. This characteristic, as well as the presence of hyperplastic blood vessels, differentiates the tumor from grade 3 astrocytomas, which do not have these features.GBMs usually form in the cerebral white matter, grow quickly, and can become very large before producing symptoms. Fewer than 10% form more slowly following degeneration of low-grade astrocytoma or anaplastic astrocytoma. These are called secondary GBMs and are more common in younger patients (mean age 45 versus 62 years). The tumor may extend into the meninges or ventricular wall, leading to high protein content in the cerebrospinal fluid (CSF) (> 100 mg/dl), as well as an occasional pleocytosis of 10 to 100 cells, mostly lymphocytes. Malignant cells carried in the CSF may spread (rarely) to the spinal cord or cause meningeal gliomatosis. However, metastasis of GBM beyond the central nervous system is extremely unusual. About 50% of GBMs occupy more than one lobe of a hemisphere or are bilateral. Tumors of this type usually arise from the cerebrum and may exhibit the classic infiltration across the corpus callosum, producing a butterfly (bilateral) glioma. Glioblastoma classification
Brain tumor classification has been traditionally based on histopathology at macroscopic level, measured in hematoxylin-eosin sections. The World Health Organization published the first standard classification in 1979 and has been doing so since.
A clinical phase-I/II study with glioblastoma patients in Brazil investigated the natural compound perillyl alcohol for intranasal delivery as an aerosol. The results were encouraging and, as of 2016, a similar trial has been initiated in the United States. Cannabinoids
The efficacy of cannabinoids (cannabis derivatives) is known in oncology (through capsules of tetrahydrocannabinol (THC) or the synthetic analogue nabilone), on the one hand to combat nausea and vomiting induced by chemotherapy, on the other to stimulate appetite and lessen the sense of anguish or the actual pain. Their ability to inhibit growth and angiogenesis in malignant gliomas in mouse models has been demonstrated. The results of a pilot study on the use of THC in end-stage patients with recurrent glioblastoma appeared worthy of further study. A potential avenue for future research rests on the discovery that cannabinoids are able to attack the neoplastic stem cells of glioblastoma in mouse models, with the result on the one hand of inducing their differentiation into more mature, possibly more "treatable" cells, and on the other hand to inhibit tumorigenesis. See also
Adegramotide
List of people with brain tumors

References
External links

Information about Glioblastoma Multiforme (GBM) from the American Brain Tumor Association
AFIP Course Syllabus – Astrocytoma WHO Grading Lecture Handout