CNS Neoplasms Flashcards
The majority of Primary (Intrinsic) CNS tumors arise from cells of which lineage?
Neuroectodermal lineage
Are meningeal tumors more common in adults or children?
Adults
What are the 5 most common primary tumor sites to metastasize to the CNS?
- Lung
- Breast
- Melanoma
- Kidney
- GI tract
What grade is Pilocytic Astrocytoma?
WHO Grade I
What grade is Diffuse Astrocytoma?
WHO Grade II
What grade is Glioblastoma?
WHO Grade IV
What grade is Oligodendroglioma?
WHO Grade II
What grade is Anaplastic Oligodendroglioma?
WHO Grade III
What grade is Anaplastic Astrocytoma?
WHO Grade III
What grade is Choroid Plexus Papilloma?
WHO Grade I
What grade is Ependymoma?
WHO Grade II
What grade is Anaplastic Ependymoma?
WHO Grade III
What grade is Medulloblastoma?
WHO Grade IV
Are meningiomas and schwannomas well-demarcated or infiltrative?
Well-demarcated
What is the most common CNS neoplasm in children?
Pilocytic Astrocytoma (Grade I)
What are the usual sites of pilocytic astrocytoma?
Cerebellum, optic pathway, hypothalamus, also thalamus, spinal cord, temporal lobe
Is pilocytic astrocytoma well-circumscribed or infiltrative?
Well-circumscribed; often forms cysts
What is the genetic underpinning of pilocytic astrocytoma?
BRAF:KIAA fusion –> leads to a more indolent tumor because of senescence (this fusion = good prognosis!)
What is the mean age range for diagnosis of diffuse astrocytoma?
30s-40s
What is the common location of diffuse astrocytoma?
Cerebral hemispheres; rarely posterior fossa
Is diffuse astrocytoma infiltrative or well-demarcated?
Infiltrative - usually not fully excised
Is a diffuse astrocytoma tumor homogenous or heterogeneous in its astrocytic cell types?
Heterogeneous - with a predominance of fibrillary astrocytes
What is the mean age for diagnosis of anaplastic astrocytoma?
45 years
What is the common location of anaplastic astrocytoma?
Cerebral hemispheres
What is prognostic for anaplastic astrocytoma?
Mitotic activity
What is the genetic underpinning of diffuse astrocytomas?
IDHI mutation + no LOH 1p,19q + p53 mutation
What age group is most common for diagnosis of oligodendroglioma?
Young adults
What is the common location of oligodendrogliomas?
Cerebral white matter - but quickly infiltrates overlying cortex
How does oligodendroglioma usually present clinically?
Seizures
What is the histological appearance of oligodendrogliomas?
“Chicken wire” vascular pattern and “fried egg” appearance (round nuclei and little cytoplasm)
What is the genetic underpinning of oligodendrogliomas?
LOH 1p,19q
What is the mitotic rate of oligodendrogliomas?
Minimal or absent
What is the mean age of onset for diagnosis of anaplastic oligodendroglioma?
48 years
What is the histological difference between oligodendrogliomas and anaplastic oligodendrogliomas?
Anaplastic oligodendrogliomas has increased cellularity, nuclear atypia, and mitoses.
Does the LOH 1p,19q of oligodendrogliomas and anaplastic oligodendrogliomas lead to a better or worse prognosis? Why?
Better prognosis!! More sensitive to chemotherapy and radiotherapy.
What is the mean age for diagnosis of glioblastoma?
50s-60s
What is the common location for glioblastoma?
Cerebral hemispheres
What are the characteristics of glioblastoma?
Infiltrative, hemorrhagic, vascular proliferation, necrotic
What is the median survival for glioblastoma?
Just a few years :(
Can glioblastoma be cured by surgical resection?
No. Appears well-demarcated but in fact is not.
What age group do ependymomas affect?
Children; especially when 4th ventricle is involved
Which tumors are often calcified?
Pilocytic astrocytomas, gangliogliomas, oligodendrogliomas, & ependymomas.
When adults have ependymomas, where are they located most often?
Spinal cord
What is a defining feature of “ependymal” differentiation?
Perivascular pseudorosettes
Choroid plexus papillomas (in children) are most commonly located where?
Lateral ventricles
Choroid plexus papillomas (in adults) are most commonly located where?
4th ventricle
What is the most common malignant brain tumor in children?
Medulloblastoma
What is the peak age range for medulloblastoma?
3-8 years old
What is the survival rate of medulloblastoma?
~50%
How do patients with medulloblastoma present?
Increased ICP, headache, vomiting, pailledema, gait disturbances, nystamus, dysmetria
Does medulloblastoma metastasize past point of origin?
Yes! Exception to the general trend that CNS tumor infiltrate only the CNS. It spreads through CSF pathways.
Mutations in the SHH gene can lead to what type of CNS tumor?
Medulloblastoma
Meningiomas are mostly which WHO grade?
I, treatable
Are meningiomas and mesenchymal tumors more common in childhood or adulthood?
Adulthood
Which cranial nerves use Schwann cells to make their myelin?
Cranial nerves 3-12
Are Schwannomas (aka neurofibromas) mostly benign or malignant?
Benign
What is the most common site for medulloblastoma?
Cerebellar vermis
Are metastases to the brain usually infiltrative or well-demarcated?
Well-demarcated
