TUMORS NEW Flashcards
OLD CLASSIFICATION OF CNS TUMORS

OLD CLASSIFICATION OF CNS TUMORS

OLD CLASSIFICATION OF CNS TUMORS

OLD CLASSIFICATION OF CNS TUMORS

The glioblastomas are largely defined by the features of
________ and _______of nonneural elements such as
vascular proliferation and are set apart from anaplastic
astrocytomas on the basis not only of their histology but
also by a later age of onset than astrocytoma and a more
rapid course.
necrosis and anaplasia
For many years, thinking about the pathogenesis ofprimary CNS tumors was dominated by the _________________of Bailey and Cushing, which was based on the
assumed embryology of nerve and glia cells.
histogenetic theory
One prominent theory was that most tumors arise from neoplastic transformation of mature adult cells ________
dedifef rentiation
In fact, the cells of origin of the major types of brain
tumors have not been unequivocally identified or, in many
cases, they appear to arise from_____________
that reside in the brain
pluripotential stem cells
Medulloblastomas, polar spongioblastomas,
optic nerve gliomas, and pinealomas occur mainly
before the age of ________years, and meningiomas and glioblastomas are most frequent in the _______decade of life.
20
sixth
The _________associated with neurofibromatosis and
tuberous sclerosis and the cerebellar hemangioblastomas
of _________are the best examples of a genetic
determinant
gliomas
von Hippel-Lindau
The rare familial disorders of multiple endocrine
neoplasia and multiple hamartomas are associatedwith an increased incidence of ________ and ________respectively
anterior pituitary tumors
and meningiomas,
Because of this capacity to transform the cellular genome, the virus product is called an________
oncogene;
Because of this capacity to transform the cellular genome, the virus product is called an_________
oncogene;
More recently, single nucleotide polymorphisms
have been identified that in combination predispose to
certain childhood tumors such as _________, or to
the more aggressive forms of various tumors
neuroblastoma
over 50 percent of astrocytomas have deletions within this gene
tumor suppressor gene p53 on chromosome 17p;
mutations in the genes that code for __________are common in gliomas and oligodendrogliomas
and their presence relates to less tumor progression.
isocitrate dehydrogenase(IDH1
and 2)
oligodendrogliomas that have combined deletions in
___________respond well to chemotherapy
and this property increases survival
chromosomes 1p and 19q
various changes such as the amplification of the
__________oncogene has been associated with an aggressive clinical course and poor outcome in neuroblastoma and
medulloblastoma.
MYCN
approximately 50 percent of gliomas there is an overexpression or a mutant form of________ and ____________ suggesting a role for these in the progression of certain tumor types.
epidermal growth factor receptor (EGFR) and of plateletderived transforming growth factor receptor (PDGFR),
These high-grade gliomas account for approximately 20
percent of all intracranial tumors and for more than 80
percent of gliomas of the cerebral hemispheres in adults
GBM and Anaplastic Astrocytoma
The peak incidence is in middle adult life (mean age for
the occurrence of glioblastoma is approximately ______years, and ________years for anaplastic astrocytoma
60
46
In GBM,
Extraneural metastases, involving ___________, are very
rare; usually they occur only after a craniotomy
bone and lymph nodes
Approximately _______percent of glioblastomas
occupy more than one lobe of a hemisphere; between
_______percent show multicentric foci of growth and
thereby simulate metastatic cancer.
50
3 and 6
Gross appearance of GBM
The tumor has a variegated appearance, being a
mottled gray, red, orange, or brown, depending on the
degree of necrosis and presence of hemorrhage, recent or
old.