Brain Tumor Frequency

MC intracranial tumors: Brain Metastases (just over 50%).
Incidence of primary brain tumors: approximately 20-30 per 100,000 in adults and 5 per 100,000 in children.
About one third of primary brain tumors in adults are malignant, whereas they account for two thirds in childhood.
Frequency of WHO subgroups and specific tumors is given (information not provided in the text).


Commonest Primary Brain Tumors by WHO Group	Commonest Primary Brain Tumors by Subtype
Meninges (37.6%) Neuroepithelial tissue (29.9%) Sellar region (16.3%) Cranial and spinal nerves (8.1%) Unclassified (5.6%) Lymphoma and hematopoietic (2.1%) Germ cell tumors and cysts (0.4%)	Meningioma (36%) Pituitary tumors (15.5%) Glioblastoma multiforme (15.1%) Nerve sheath tumors (8.1%) Diffuse astrocytoma (2.3%) Primary CNS lymphoma (2%) Ependymal (1.9%) Anaplastic astrocytoma (1.7%) Pilocytic astrocytoma (1.4%) Neuronal and neuronal mixed (1.2%) Oligodendroglioma (1.1%) Oligoastrocytoma (0.9%) Craniopharyngioma (0.8%) Anaplastic oligodendroglioma (0.5%)

Neuro-Oncology