Term
|
Definition
3 main types of herniations occur in the brain
due to increased pressure - e.g. from a growing tumor
-subfalcine herniation of cingulate gyrus
-uncal herniation
-transforaminal herniation of cerebellar tonsil |
|
|
Term
|
Definition
| transtentorial herniation of middle part of temporal lobe |
|
|
Term
|
Definition
| because the skull sutures haven't close, the tumor can grow unrestricted and herniation is much less likely |
|
|
Term
| classification names of CNS tumors |
|
Definition
-meningeal
-glial
-embryonal
-neuronal
-tumors of CN and PN
-hematopoietic |
|
|
Term
| histological grading of tumors |
|
Definition
correlates with biologic behavior of a tumor
it is a key factor in choosing therapeutic alternative (surgery, radiation, chemo)
*WHO grades I-IV* |
|
|
Term
|
Definition
low proliferative potential
usually slow growing
possibility of cure with surgical resection alone |
|
|
Term
|
Definition
generally infiltrative
often recur
may progress to higher grades with time |
|
|
Term
|
Definition
histological evidence of malignancy (e.g. nuclear atypia, brisk mitotic activity)
patients will often receive adjuvant radiation and/or chemotherapy |
|
|
Term
|
Definition
cytologically malignant, mitotically active, necrosis
often associated with rapid pre-postoperative evolution and fatal outcome |
|
|
Term
|
Definition
usually slow growing tumors; brain adapts around it
arise from meningothelial cells in the leptomeninges (pia mater and arachnoid mater)
intraspinal meningiomas F>M 10:1
often attached to the dura (may see dural tail) |
|
|
Term
|
Definition
previous radiotherapy
hormonal dependent neoplasms (breast, endometrial)
neurofibromatosis type 2 |
|
|
Term
meningioma
histological features |
|
Definition
syncytial growth
whorl formation
intranuclear inclusions
psammoma bodies (laminated, calcified) |
|
|
Term
|
Definition
most are grade I with 7-25% of recurrence
-complete resection is the most important factor to prevent recurrence
grade II and III meningiomas exist and have high recurrence rates; usually require adjuvant radiation/chemo |
|
|
Term
|
Definition
astrocytic
oligodendroglial
ependymal |
|
|
Term
|
Definition
two categories:
Circumscribed - grade I, II
Inflitrative - grade II, III, IV |
|
|
Term
| circumscribed astrocytic glial tumor |
|
Definition
WHO grade I or II
can be completely excised withOUT a high likelihood of recurrence
-->Pilocytic Astrocytoma |
|
|
Term
pilocytic astrocytoma
epidemiology
locations |
|
Definition
astrocytic, circumscribed, glial tumor, WHO grade I
*mainly in children and young adults*
cerebellum, optic nerve, optic chiasm/hypothalamus, temporal lobe
associated with neurofibromatosis type I |
|
|
Term
pliocytic astrocytoma
histological features |
|
Definition
hair-like processes
*Rosenthal fibers* dense fibers in compact area
biphasic and micro cystic change - compact & loose areas |
|
|
Term
| infiltrative astrocytic glial tumor |
|
Definition
WHO grades II, III, IV
II: diffuse astrocytoma*
III: anaplastic astrocytoma
IV: glioblastoma |
|
|
Term
infiltrative astrocytic glial tumor
histological features |
|
Definition
micro cysts
perineuronal satellitosis (cells around neurons)
perivascular satellitosis
subpial aggregates
white matter tract infiltration |
|
|
Term
diffuse astrocytoma
characteristics/location |
|
Definition
infiltrative astrocytic glial tumor, WHO grade II
slow growth; preferentially supretentorial (in cerebrum); tendency to progress; non-enhancing lesions |
|
|
Term
diffuse astrocytoma
mean age of diagnosis |
|
Definition
| mean age of dx = 34 years |
|
|
Term
|
Definition
| mild increase in cellularity compared to normal brain |
|
|
Term
anaplastic astrocytoma
characteristics/location |
|
Definition
infiltrative astrocytic glial tumor, WHO grade III
most common in cerebral hemispheres
2/3 enhancing lesions |
|
|
Term
anaplastic astrocytoma
mean age of diagnosis |
|
Definition
| mean age of dx = 45 years |
|
|
Term
anaplastic astrocytoma
histo |
|
Definition
hyper cellularity
nuclear atypia; more pleomorphic nuclei
significant proliferative activity |
|
|
Term
glioblastoma
characteristics |
|
Definition
infiltrative astrocytic glial tumor, WHO grade IV
ring enhancing with central necrosis
poor prognosis, improving with new therapies |
|
|
Term
glioblstoma
mean age of diagnosis |
|
Definition
mean age of dx = 61 years
most frequent brain tumor in adults |
|
|
Term
|
Definition
microvascular proliferation
necrosis
butterfly lesion
most cellularity |
|
|
Term
| pathologic progression/development of infiltrating astrocytomas |
|
Definition
| astrocytes or precursor stem cells can differentiate directly into a primary/de novo glioblastoma or go through a progression starting with low-grade astrocytoma and going onto either a secondary glioblastoma or a anaplastic astrocytoma and then secondary glioblastoma |
|
|
Term
oligodendroglial glial tumors
epidemiology |
|
Definition
uncommon in childhood
occur most frequently in patients aged 30-50 years |
|
|
Term
oligodendroglial glial tumor
characteristics |
|
Definition
more prone to hemorrhage than other gliomas
WHO grade II and III, but in general better prognosis than the same grade astrocytoma |
|
|
Term
oligodendroglial glial tumor
histologic features |
|
Definition
infiltrative
round nuclei
>fried egg appearance
perinuclear halos
fine branching blood vessels
many have micro calcifications |
|
|
Term
| *molecular aspects of oligodenrogliomas* |
|
Definition
*loss of 1p (short arm on chromosome 1)
*loss of 19q (long arm on chromosome 19)
*better response to chemo and better survival reponse with loss of 1p and 19q |
|
|
Term
|
Definition
WHO grades I, II, III
grade II: classic ependymoma
grade III: anaplastic ependymoma |
|
|
Term
classic ependyoma & anaplastic ependyoma
characteristic/location |
|
Definition
grade II (classic) and III (anaplastic) ependyoma glial tumors
intracranial neoplasm of childhood
intraventricular
most common in posterior fossa
*well-circumscribed |
|
|
Term
classic ependyoma & anaplastic ependyoma
mean age |
|
Definition
mean age = 4 years
present with increased ICP, hydrocephalus |
|
|
Term
ependyoma glial tumors
histo |
|
Definition
psuedorosettes = tumor aligns along blood vessel
ependymal rosettes and canals |
|
|
Term
|
Definition
|
|
Term
|
Definition
-embryonal CNS tumor
-primarily in children
-tendency to disseminate through CNS
-generally arises from the vermis and fills the 4th ventricle
-presents as increased intracranial pressure symptoms
*WHO grade IV
-rapidly fatal if untreated
-current therapy achieves 5 yeah PFS (progression-free survival) of 50-80% |
|
|
Term
|
Definition
small, undifferentiated cells
high mitotic index and widespread apoptosis
may form Homer Wright rosettes |
|
|
Term
|
Definition
Schwannoma
neurofibroma
MPNST |
|
|
Term
|
Definition
-neurilemmona; acoustic neuroma
-Schwann cells proliferate and push away axon
-discrete contrast enhancing +/- cystic
-bilateral acoustic schwannomas associated with type 2 neurofibromatosis
-do not infiltrate the nerve of CNS
-WHO grade I |
|
|
Term
|
Definition
verocay bodies
Antoni A and B areas
-areas of hyper/hypocellularity
basal membrane deposition |
|
|
Term
|
Definition
infiltrate the nerve
WHO grade I
plexiform NF affects large plexus
10% have malignant transformation |
|
|
Term
|
Definition
hypocellular lesion
proliferation of: Schwann cells, perineurial cells, fibroblasts, blood vessels, mast cells
spindle nucleus Schwann cells mixed with other cells |
|
|
Term
malignant peripheral nerve sheath tumor
MPNST |
|
Definition
usually arises from pre-existing plexiform neurofibroma
associated with prior radiation
WHO grade III or IV
3rd-6th decode of life |
|
|
Term
|
Definition
sarcoma looking
geographic necrosis
high mitotic activity |
|
|
Term
|
Definition
|
|
Term
|
Definition
occurs sporadically and in immunocompromised patients
**EBV plays an important role of development in 95% of immunocompromised patients**
forms a large, enhancing intraparenchymal mass; may be multicentric
(lymphomas which arise outside the NS may infiltrate meninges, but usually do not form masses) |
|
|
Term
primary CNS lymphoma
histo |
|
Definition
often show angiocentric growth
tumor cells have big nuclear:cytoplasm ratio
cells are dyshesive
monoclonal proliferation of lymphoid cells, most often B-cells
nuclei arrange around vessels and infiltrate out |
|
|
Term
| metastatic tumors to the CNS |
|
Definition
usually develop from hematogenous spread
-lung, breast, renal, colon carcinomas
-melanoma
rarely by direct extension (head and neck)
often multiple, in the gray/white junction or meninges
form a distinct margin with adjacent brain |
|
|
Term
| which tumors are WHO grade I |
|
Definition
pilocytic astrocytoma
myxopapillary ependymoma
Scwannoma
neurofibroma |
|
|
Term
| which tumors are WHO grade II |
|
Definition
astrocytomas
oligodendroglioma (fried egg, 1p19q)
classic ependymoma |
|
|
Term
| which tumors are WHO grade III |
|
Definition
anaplastic astrocytoma
anaplastic ependymoma |
|
|
Term
| which tumors are WHO grade IV |
|
Definition
glioblastoma (malignant)
medulloblastoma (small round blue cell tumor) |
|
|
