Term
An adult patient presents with new onset seizures, subacute development of neurological symptoms, dizziness and ataxia.
You order an MRI. What do you most likely see? |
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Definition
Metastatic brain lesions. NOT primary tumors and rare in kids
1) Adenocarcinoma (lung, breast, colon)
2) Small cell carcinoma (lung)
3) Melanoma |
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Term
A 5 year old male presents with headache, nausea/vomiting and papilloedema. There is also notable truncal and appendicular ataxia.
You run some tests and discover a primary brain tumor. What kinds of tumors could it be? |
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Definition
Pediatric population has 70% of tumors in the posterior fossa (infratentorial)
1) Pilocytic astrocytoma (cerebellar astrocytoma)******
- Low grade
2) Medulloblastoma (posterior fossa)
- High grade
- Type of Primitive Neuroectodermal Tumor (PNET)
- 70 % 10 year survival if no CSF spread! |
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Term
| What are the most common types of primary brain tumors? |
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Definition
1) Astrocytoma
- Pilocytic (low grade)
- Anaplastic
-Glioblastoma multiforme (high grade)
2) Primitive neuroectodermal tumors (PNETs)
- medulloblastoma (kids)
3) Meningiomas
4) Pituitary Adenomas |
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Term
| What clinical symptoms suggest a primary brain tumor? |
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Definition
1) Increased ICP
2) Seizures
3) Focal neurlogical deficits
4) Hormonal changes (pituitary adenoma)
5) Visual changes (diplopia, field defects- Pituitary adenoma on optic chiasm |
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Term
| What kind of tumor do you find in the brainstem (pons)? |
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Definition
Pontine glioma (high-grade astrocytoma)
- No biopsy, just treat with chemo. |
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Term
| What kind of tumor do you find in the spinal cord? |
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Definition
| Low-grade astrocytomas (grade 1 and II) |
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Term
A patient presents with headache, nausea and papilloedema, as well as seizures.
You order a CT and discover a mass right next to the 3rd ventricle.
What type of tumor could this be? |
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Definition
1) Pilocytic astrocytoma (low grade)
2) GBM (high grade) |
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Term
| What types of tumors might you find within the cerebral hemispheres? |
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Definition
1) Grade II-III astrocytomas
2) GBM (crosses corpus callosum) |
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Term
| Which brain tumors are treated without biopsy? |
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Definition
1) Optic Nerve gliomas in NF-1
2) Pontine gliomas |
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Term
| What characteristics determine whether a brain tumor is high or low grade? |
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Definition
1) Growth Rate
2) Invasiveness
3) Resectable
Low Grade= Pilocytic astrocytoma, Pituitary adenoma, Meningioma
High Grade= Glioblastoma (adults), Medulloblastoma (kids- will metastasize) |
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Term
Describe the W.H.O grading system for tumors.
What is the life expectancy of grades 1-4? |
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Definition
Most important for astrocytomas
1) Very benign, often curable (Pilocytic astrocytoma)
- >75% survival, 10 year
2) Slow-growin, maybe curable (astrocytoma, meningioma)
- Median= 80 months
3) Rapid progression, not usually curable (Anaplastic astrocytoma, anaplastic meningioma)
- Median= 21 months
4) Very rapid growth, poor prognosis (GBM, Medulloblastoma)
- Median= 11 months |
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Term
| What are the major types of Non-neuroglial CNS tumors? What is their prognosis? |
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Definition
1) Meningioma (II-III)
- Generally long time (may have multiple resections)
2) Pituitary Adenoma (II)
- 90% >10 year survival |
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Term
| What is the relationship between tumor grade and prognosis? |
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Definition
VARIABLE.
Can have low-grade tumor in non-resectable area, making prognosis very bad (i.e. thalamus and pons)
ex). GBM (IV) is 5% 5 year survival, but Medulloblastoma (IV) is 50%.
also, 3rd ventricle pilocytic astrocytomas cannot be resected |
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Term
| What are the important pathological features of a Pilocytic astrocytoma? |
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Definition
Grade 1 astrocytoma found in Cerebellum, thalamus and/or optic nerve of kids (>75% at 10 years)
1) Discrete, well circumscribed
2) Associated cystic area (except optic nerve gliomas in NF-1)
3) Contrast enhancing
4) Biphasic (piloid cells and microcystic areas), with Rosenthal fibers (red spots) and NO mitoses. |
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Term
| What are the important pathological features of a diffuse astrocytoma (grade II) |
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Definition
Grade II tumor found in adults as Diffusely infiltrating astrocytoma of cerebral hemispheres.
1) Mass effect but NO contrast enhancement
2) Histologically
- increased cellularity (still low)
- MIld nuclear pleomorphism
- Clustering of astrocytes
- NO mitorses |
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Term
| What are the important pathological features of a n Anaplastic Astrocytoma? |
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Definition
Grade III tumor found in adults as diffusely infiltrating astrocytoma of cerebral hemispheres (like diffuse astrocytoma)
1) 50 % show contrast enhancement
2) Histologically
- Marked increase in cellularity
- Increased pleomorphism
- Mitoses |
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Term
You are the pathologist who receives a tumor biopsy from a patient's left cerebral hemisphere.
It appears to be highly cellular, with increased nuclear pleomorphism. Mitotic bodies are present, but there is no necrosis or endothelial proliferation. |
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Definition
Anaplastic Astrocytoma (Grade III)
Cellularity and Pleomorphism could indicate diffuse or anaplastic astrocytoma, but presence of Mitoses gives it away!
Absence of necrosis and endothelial proliferation rules out glioblastoma multiforme. |
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Term
| What are the important pathological features of a Glioblastoma? |
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Definition
Grade IV tumor in adults (sometimes children) that occurs as a diffusely infiltrating glial tumor of the cerebral hemispheres that CROSSES the corpus coallosum
1) Contrast enhancing
2) Histologically
- Densely cellular
- Marked Pleomorphism
- Numerous mitoses ***
- Endothelial proliferation ***
- Necrosis with pseudopallisading *** |
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Term
| What are the important pathological features of Medulloblastomas? |
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Definition
PNET of posterior fossa in children
1) Histologically
- Densely cellular "small blue cell tumor"
- Numerous mitoses
- Apoptotic cells (karyrrhectic)
- Endothelial proliferation
- Necrosis
- Neuronal or glial differentiation
- Homer Wright rosettes
- GFAP positive cells |
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Term
| What are the important pathological features of a Meningioma? |
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Definition
Discrete, non-invasive tumor located extra-axially that pushes into brain.
1) Attached to dura (invasion of skull common- Hyperostosis)
2) HIstologically
- Fibroblastic
- Meningothelial whorls
- Psammoma bodies |
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Term
| What are the important pathological features of a Pituitary adenoma? |
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Definition
Tumor or adenohypophysis (anterior lobe) found in sella turcica (anterior pituitary)
- Can be null (common) or hormone secreting (rare)
- Hormone secreting can be prolactin, Growth hormone (acromegaly), ACTH (Cushing's)
1) Histologically
- Monomorphic, cellular proliferation
- Loss of normal pituitary architecture
- Mitoses are rare |
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Term
A patient presents with bilateral acoustic neuroma, multiple meningiomas and ependymomas (spinal cord).
What hereditary syndrome do they have? |
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Definition
| Neurofibromatosis Type II (usually adult-onset) |
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Term
A patient presents with "care-au-lait spots," dermal neurofibromas, bilateral optic nerve gliomas (pilocytic astrocytoma of optic chiasm) and a malignant peripheral nerve sheath tumor.
What hereditary syndrome do they have? |
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Definition
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Term
| Explain the molecular evolution of Glioblastoma Multiforme |
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Definition
1) Primary GBM
- EGFR amplification
- LOH chromosome 10q (mutation of PTEN)
- NO loss of p53
2) Secondary GBM
- P53 mutation (LOH at chromosome 17p)
- Grade II progression to grade III to grade IV
- PDGFR-alpha over-expression or amplification |
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Term
| What types of tumors are EGRF and p53 associated with? |
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Definition
1) EGFR amplification/overexpression is seen in primary GBM, along with LOH at chromosomes 10q
- Transmembrane receptor ...MAPK signaling..division..ect.
2) p53 mutation is earliest step in Secondary GBM (LOH chromosome 17p)
- Activated by DNA damage and shuts down DNA division
- Mutation leads to abnormal proliferation and buildup of protein. |
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Term
| How can you tell between a primary brain tumor and a single metastesis? |
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Definition
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Term
| What are the 3 most common primary brain tumors in adults? |
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Definition
1) Astrocytoma
- astrocytoma (II), anaplastic astrocytoma (III), GBM (IV)
2) Meningioma
3) Pituitary Adenoma |
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Term
| Name 3 histological features that define Glioblastoma |
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Definition
1) Necrosis (pseudopallisading)
2) Endothelial proliferation
3) Numerous Mitoses |
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Term
| What 2 primary brain tumors are most common in children? |
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Definition
1) Medulloblastoma (IV)
2) Pilocytic astrocytoma (I) |
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Term
| Which 2 hereditary syndromes are associated with brain tumors? |
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Definition
1) NF1
- Bilateral optic nerve glioma (JPA optic chiasm)
- Plexiform neurofibromas (can become malignant peripheral nerve sheath tumors)
2) NF2
- Meningiomas
- Bilateral acoustic neuromas
- Ependymomas |
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Term
| What is the most intelligent course of treatment for a patient with multiple metastases throughout the brain? |
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Definition
| MAYBE chemo, but probably hospice care. |
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Term
| What does the level of EGFR amplification tell you about the likely sensitivity of a patient with primary GBM to treatment? |
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Definition
| The greater the amplification, the more sensitive! |
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Term
| What does the level of P53 over-expression tell you about the prognosis of a patient with secondary GBM? |
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Definition
| The more over-expression, the worse the prognosis. |
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