CNS Tumors Flashcards
What are the 3 types of gliomas?
astrocytomas
oligodendrogliomas
ependymoma
Are most tumors of the CNS primary or metastatic?
metastatic - 70%!
What is the most common primary brain tumor in adults?
glioblastoma multiforme
What are the general characteristics of a metastatic tumor to the brain?
generally well circumscribed
often multiple
usually located in junction between gray and white matter
What are the general characteristics of a primary brain tumor?
poorly circumscribed
usually single
location varies by type
Where do metastatic brain tumors often come from?
lung, bladder, breast, melanoma and others
What does pleomorphic mean?
It means the cells come in many different odd shapes - it’s generally not a good sign
How common are CNS tumors in children? Which are most common in children?
In general, CNS tumors are the 2nd most common neoplasia in children
medulloblastoma and astrocytoma are the most common types
As for the location in the CNS, where do adult CNS tumors occur and where to childhood CNS tumors occur?
children - 70% posterior foss
adults - 70% supratentorial
What does the WHO base it’s grading scale on?
mostly histological appearance
What are the 4 WHO grades?
1 - low proliferative potential, possible to cure wiht resection
2 - infiltrative, but low proliferative activity
3- evidence of malignancy = nuclear atypia and much mitotitc activity
4 - cytologically malignant, mitotically active, necrosis prone
What are the survival estimates for grade 2, 3, and 4?
2 = greater than 5 years
3: 2-3 years
4 = depends on treatment, but often not more than a year
What do gliomas arise from?
ASTROCYTES
oligodencrocytes
ependymal cells
what is the highest-grade astrocytoma?
glioblastoma
What are the most common symptoms of a glioma
it depends on location of tumor obviously, but headaches, seizures, memory loss and changes in behavior are common
What do you call a grade 1 astrocytoma?
pilocytic astrocytoma
low proliferative potential
Are pilocytic astrocytomas more common in chidlren or adults, and where in the brain d they usually occur?
children - frequently posterior fossa - cerebellum
What are the morphologic features of pilocytic astrocytomas?
ofen cystic
bipolar cells with long hair-like processes
rosenthal fibers**
biphasic
What genetic point is associated with pilocytic astrocytoma?
a BRAF and KIAA fusion/duplication - diagnosed with FISH
they have a worse prognosis
What is a grade 2 astrocytoma?
diffuse astrocytoma
What is the main characteristic of a diffuse astrocytoma?
it’s actually very slowly progressive, but it will almost always eventually become anaplastic
Which type of diffuse astrocytoma is most likely to progress to a grade 3?
gemistocytic astrocytoma
What is the grade 3 astrocytoma called?
anaplastic astrocytoma
What are the characteristics of an anaplastic astrocytoma?
Starting to be much more cellular and pleomorphic. Often has GFAP (glial fibrillary acidic protein) as an intermediate filament
