Flashcards in Lecture 8 and 12 -- CNS Tumors + Path Deck (32):
what is the most common malignancy to the brain?
Metastatic disease -- 50% from the Lung
where do most ped tumors occur? where do most adult tumors occur?
Peds -- 75% in Posterior Fossa
Adults -- 75% in cerebral hemispheres
WHO grading system (using astrocytoma as an example; describe the progression and associated micropath at each grade)
Grade 1 -- ?
Grade 2 -- Diffuse Astrocytoma -- some atypical cells but no mitotic activity
Grade 3 - Anaplastic Astrocytoma -- Increased cellularity and mitotic activity
Grade 4 - Glioblastoma -- vascular proliferation/endothelial patches, necrosis, pseudopalisading
What is meant by the term "diffuse"?
infiltrate the brain as individual cells; wonder out into the brain parenchyma
therefore technically non curable and start as grade 2 tumors
pathognomonic micropathology finding?
Primary vs secondary glioblastomas?
Primary -- Preseents as glioblastoma, not an evolving precursor lesion.
Secondary -- Evolves from Precursors
Median survival and pathogenesis?
marker to test for?
the most common Primary CNS Malignancy
<12 month median survival. Characteristic rapid progression, significant mass effect, edema
Treatment: Cannot resect
Tx = Radx + Temozolomide
What is the significance of an MGMT mutation for Glioblastoma treatment?
MGMT negates the effect of Temozolomide
therefore if there is an MGMT methylation, the gene is silenced and patient responds better to Temozolomide therapy
Unmethylated MGMT = negative prognostic factor (irrespective of treatment)
Anaplastic oligodendroglioma --
genetic mutation/marker ?
Friend Egg with Chicken wire
1p/19q Co Deletion -- positive prognostic factor
name 3 low grade gliomas ?
what is the standard therapy?
what is the median survival time?
§ Diffuse astrocytoms -- 5 years
Oligoastrocytoma -- 7.5 years
Oligodendroglioma -- 10 years
13.3 year Median Survival -- with RT + PCV
Gross path ?
buzzword for histo path?
more common peds tumors
Gross Path - well demarcated lesions
Pseudorossettes -- lack true lumen
Rossettes -- True Lumen
• Myxopapillary Ependymoma --
where does it occur?
benign vs malignant?
benign lesion of the filum terminale
Sx -- back pain
pituitary Adenomas --
where do they occur?
presenting symptoms related to this location?
what percentage are secretory?
10-15% of all CNS neoplasms
Arise in Sela Tursica
Can lead to diplopia/bitemporal hemianopia
70% are secretory
Treatment for prolactinoma?
Treatment for GH secreting tumor?
Prolactima -- Dopamine Agonists (Bromocriptin, Cabergoline)
GH secreting tumors -- Octreotide (somatostatin analog)
- how common is it?
- from what cells do they originate? where do they arppear?
The most common benign CNS Primary (90% are benign)
- Arise from arachnoid cap cells
- commonly at the dural base and well circumscribed
-- Loss of 22q12.2 tumor suppressor (including Merlin/Schwannoma)
-- Histo: "Whorls" and Psammoma bodies
what is the best predictor of failure/recurrence?
STR + External Beam Radiation
• Extent of the resection is predictor of failure
name 4 childhood primary tumors
Pilocytic Astrocytoma (benign, good prognosis)
Ependyoma (poor prognosis)
Pilocytic Astrocytoma --
where does it commonly occur?
Posterior Fossae (Cerebellum)
Gross Path; Cystic appearance with "mural nodule"
Histo Path? Biphasic Architecture + rosenthal Fibers
classified as a ...?
where does it occur?
Tendency for what other manifestation?
Primitive Neuroendocrine Tumors (PNET), but occurs in the cerebellum and therefore Medulloblastoma
Gross Path -- Poorly circumscribed with necrotic hemorrhage
Histopath -- Homer Write Pseudorossettes
Tendency for CSF obsturction leading to hydrocephalus
Progression: disease is very aggressive and spreads through the CSF
Treatment: Surgical treatment followed by Craniospinal Radiation and Chemotherapy
- who gets these tumors?
- benign vs malignant?
- Arises from what embryological structure?
Benign tumor of children, but there is bimodal distribution and adults can get them too
Arise from remnants of Rathke's Pouch
Treatment: GTR > STR + RT
associated with what familial disease?
where does it commonly present?
produces what hormone?
A/w Von Hippel Lindau
imaging: Cystic Mural nodule in the cerebellum
Can produce EPO and lead to secondary polycythemia
Histo: Thin walled capillaries with minimal intervening parenchyma
what is the classic peripheral nerve sheath tumor?
8th cranial nerve schwannaoma
8th cranial nerve schwannoma
- where is the lesion seen on imaging?
commonly seen in what tumor syndrome?
aka Vestibular schwannoma
Imaging: Cerebellopontine angle;
Antoni A -- pink with "Verocay bodies" --- (the nuclear free zones)
Antoni B -- pale
Commonly seen with NF2
Treatment for Vestibular schwanomma ?
risk of the treatment
If unilateral -- Surgery
Risk - Deafness
If Bilateral -- Bevacizumab;
Name 4 tumor syndromes ?
Von Hipple Lindau
Associated lesions ?
Loss of Neurofibromin Gene (tumor suppressor gene)
lesions -- Cafe Au Lait, Lisch Nodules of the Iris, skin tumors, pheocromocytoma
Plexiform neurofibroma --
NeuroFibromatosis Type 2
- genetic mutation?
- Classic Tumor ?
merlin/schannomin (tumor suppressor loss)
Specific for Bilateral 8th nerve schwannomas
Tuberous Sclerosis --
CNS Lesions ?
Two genes which comprise a tumor suppressor complex; either can be mutated (chromosome 9 or chromosome 16)
CNS lesions --- cortical tubers; subependymal nodules, subependymal giant cell astrocytomas (obstructing outflow)
Present with Seizures
Von Hipple Lindae Disease
what other locations may tumors be outside the CNS
hemangioblastomas of the CNS
Renal cell carcinomas, Pheochromocytoma
○ Loss of tumor suppressor gene on chromosome 3p25.3 --- involved with HIF1 metabolism
chromosome(s) involved in Tuberous sclerosis ?
types of tumors found
9 and 16
Subependymal giant cell astrocytoma (if it obstructs CSF flow) == pathognomoninc for this disease