CNS Tumors - Bemis Flashcards
What are the general differences between primary brain tumors and metastasis to the brain from other primary?
- Primary brain tumors
- poorly circumscribed
- usually single (infiltrated)
- location varies by specific type
- Metastasis to the brain
- generally well circumscribed
- often multiple
- usually located in the junction between gray and white matter
What are the features of WHO Grade 1 brain tumors?
- Generally **low proliferative potential **
- Possible to cure following resection alone
- not rapidly growing
- ex. meningiomas
What are the features of WHO Grade 2 brain tumors?
- Generally infiltrative, but low proliferative activity
- If removed will often recur
- tumor is starting to wind its way into other areas of the brain
What are the features of WHO Grade 3 brain tumors?
- Generally histological evidence of malignancy
- Nuclear atypia and much mitotic activity
- pleomorphic nuclei
- condensed chromosome
- separating into two
What are the features of WHO Grade 4 brain tumors?
- Cytologically malignant
- Mitotically active
- Necrosis prone
- Rapid pre- and post-operative disease progression
- Usually fatal outcome
What are the clinical features of a benign pilocytic astrocytoma?
- Grade I astrocytoma
- Mostly in children (0-19)
- Frequently = posterior fossa
- Commonly = cerebellum
- Excellent prognosis
What are the morphologic features of a benign pilocytic astrocytoma?
- Grade I astrocytoma
- Often cystic - loose spaces in it
- Bipolar cells with long hair-like processes
- Rosenthal fibers
- corkscrew morphology
- eosinophilic
- Biphasic: loose areas and dense areas
- Glial fibrillary acidic protein (GFAP) is an intermediate filament
What are the clinical features of a diffuse astrocytoma?
- Grade II Astrocytoma
- Highest prevalence 30-39
- Slowly progressive
What are the morphological features of a diffuse astrocytoma?
- Grade II Astrocytoma
- Low proliferative potential but infiltrative
- Diffuse = “fribrillary”
- Increased number of nuclei
What is the prognosis of diffuse astrocytoma?
- Grade II Astrocytoma
- Slowly progressive
- eventually, most become anaplastic (Grade III)
- Surgical diagnosis and then remove as much as possible
- Radiation to kill remaining tumor cells
- Chemotherapy not so good because cells are growing slowly
What are the morphological features of an anaplastic astrocytoma?
- Grade III Astrocytoma
- Shows more cellular regions
- cells moving into adjacent areas
- More pleomorphism, more mitoses
- glial fibrillary acidic protein (GFAP) positivity –> synthesized during gliosis (astrocyte proliferation)
How long is the clinical history from the time glial progenitor cells become primary glioblastoma?
3-6 month clinical history
In the pathway of secondary glioblastoma, how long is the clinical history from the time of diffuse astrocytoma to the progression to secondary glioblastoma?
about 5 years
In the pathway of secondary glioblastoma, how long is the clinical history from the time of anaplastic astrocytoma to the progression to secondary glioblastoma?
about 2 years
Why is it important to know whether the grade IV brain tumor is a primary glioblastoma or a secondary glioblastoma?
Can more effectively target different molecules in therapy.
What are the clinical features of glioblastoma?
- Grade IV Astrocytoma
- Most common primary brain tumor
- More common in adults (45-75 yoa)
- Most prevalent ages 60-69
- Slowly progressive neurologic deficity
- usually motor weakness
- Headache
- Seizures
- Symptoms associated with increased intracranial pressure
- headaches, N/V, cognitive impairment
What are the morphological features of glioblastoma?
- Grade IV Astrocytoma
- Variation in appearance in different areas
- Pseudopalisading Necrosis
- tumor cells try to escape necrosis
- cells angled in direction away from necrosis
- Vascular proliferation
- May cross the midline (butterfly glioma)
What is the prognosis of primary glioblastoma?
- Grade IV Astrocytoma
- Mean survival = 10 months
- Less than 10% alive at 2 years
What are the clinical features of an oligodendroglioma?
- Less common
- 10% of gliomas in adults
- may also be found in children
- Present with seizures
- Mean survival of 5-10 years
- Deletion of chromosome areas 1p and 19q improves survival
What are the morphological features of oligodendroglioma?
- Sharply circumscribed hemispheric masses
- Round nuclei with cytoplasmic halos
- perinuclear halo
- “fried egg” look
- Delicate capillary network (seen on squash prep)
- Most are calcified
What are the clinical features of an ependymoma?
- Usually in children = fourth ventricle
- Adult variant = spinal cord
- Slow growing
- Poor prognosis –> Mean: 4 years survival
- CSF dissemination common (on LP)
What are the morphological features of ependymoma?
- Solid or papillary mass
- Round nuclei
- Dense fibrillary background
- looks disorganized
- Canals, pseudorosettes, rosettes
- circumferential cell body with nucleus
- central lumen (proteins, blood vessel)
What are the clinical features of medulloblastoma?
- Grade IV
- Usually in children (0-9, M>F)
- Usually in cerebellum
- Very RADIOSENSITIVE
- Symptoms:
- Headache
- Morning vomiting (worse with time)
- May have problems with back pain and motion
What are the morphological features of medulloblastoma?
- Grade IV
- Well-circumscribed
- Small, blue, dark, round, elongated anaplastic cells
- Homer-Wright rosettes (central lumen=protein)
What are the genetic features of medulloblastoma?
Isochromosome 17 = i(17q) = POOR PROGNOSIS!
- half of chromosome duplicates
- EITHER p part is put on p
- OR q part is put on q
What are the clinical features of meningioma?
- Second most common primary brain tumor
- Benign tumor of arachnoid cells
- Slow growing
- Cured by resection
What are the morphological features of a meningioma?
- Attached to dura
- Compresses brain
- Syncytial pattern
- swirling cell bodies (like van gogh’s starry night)
- Psammoma bodies (often calcium deposits)
