Answer

Answer 20-8. Most primary brain tumors are named according to their cell of origin: glioma, ependymoma, meningioma, lymphoma (either primary or spread from elsewhere), Schwanoma, pituitary adenoma, primitive neuroectodermal tumor and pinealoma. The gliomas may be subdivided into astrocytomas (4 grades, with glioblastoma multiforme being the worst) and oligodendrogliomas.