Brain Cancer: Staging and Treatment Flashcards
What are the 4 grades of astrocytoma/glioma?
1) Juvenile Pilocytic
2) Diffuse (slow-growing, no distinct borders)
3) Anaplastic (signs of mitosis)
4) Glioblastoma (lots of mitosis, death, blood vessels)
What is Grade 1 astrocytoma/glioma? What are its characteristics?
Juvenile Pilocytic; clear border
What is Grade 2 astrocytoma/glioma? What are its characteristics? What is the survival rate?
Diffuse; slow growing, no distinct borders; 20-60% survival rate.
Why is chemotherapy no very effective for brain tumors?
Difficulty getting past the blood/brain barrier.
What is Grade 3 astrocytoma/glioma? What are its characteristics? Survival rate?
Anaplastic; signs of mitosis; 0-50%
What is Grade 4 astrocytoma/glioma? What are its characteristics? Survival rate?
Glioblastoma; lots of mitosis, necrosis, diffuse border, signs of local metastasis in brain; 4-15%
What does necrosis on an MRI tell you about a brain tumor?
It is fast-growing.
What is the survival rate for glioblastoma?
4-15%
What is the survival rate for Grade 2 (diffuse) astrocytoma/gioma?
20-60%
What is the survival rate for Grade 3 (anaplastic) astrocystoma/glioma?
10-50%
If you have no necrosis and no mitosis, but diffuse borders, what stage is the astrocytoma/glioma and what is the survival rate?
Grade II (Diffuse); 20-60%
True or false: A patient cannot survive multifocal lesions on the brain.
True
What are the two types of GBMs?
1) Primary (big tumor and fast-growing)
2) Secondary (progresses slowly)
True or false: We know the genetics of primary GBM tumors at each step of its development.
False; we only know it at the end.
True or false: We know the genetics of secondary GBM tumors at each step of their development.
True
What does Mdm2 overexpression cause in primary GBM tumors?
Deactivation of p53
What are 4 common mutations in primary GBM tumors?
1) Mdm2 overexpression
2) EGFR amplification
3) INK4A/ARF loss
4) PTEN loss
What are 4 common mutations in low-grade secondary glioma?
1) PDGF, FGF overexpression
2) p53 mutation
What mutations lead to low-grade glioma becoming anaplastic?
CDK4 amplification and Rb or INK4a/ARF loss.
What mutation sometimes leads to secondary anaplastic glioma becoming GBM?
PTEN loss (only 5% of the time)
What are two types of radiation used to treat brain cancers?
1) 3D Conformational
2) Proton Beam Therapy
What is the benefit of proton beam therapy over 3D Conformational Radiation?
The protons only affect the targeted area and leave the rest of the brain unaffected by radiation.
What type of cells are GBM tumor cells?
astrocytes
What cells are the support cells of the brain?
astrocytes
