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.
