CNS-Tumors

Question 1

General Properties (Brain tumors)

Answer 1

• 30 % become metastatic
• 70% of adult neoplasms=Supratentorial
• 70% of child neoplasms=Infratentorial (cerebellum)
• _Common highly malignant adult tumo_r=_{^{Gilblastoma multiforme}}
• Common malignant tumor in children=_{<strong>^{Medullablastoma}</strong>}
• Primary neurologlial tumor (gilomas)-
  
  • Astrocytoma & oligodendroglioma
• Primitive neuroeputhelial tumor- Medulloblastoma
• Neuronal tumor-Lymphoma
• Meningioma (arachnoid cells)

Question 2

Pilocystic Astrocytoma

Answer 2

• Genetics- TP53
• Marker-GFAP ^{(glial fibrillary acidic protein)}
  
  • _{^{<strong><u>Fibrillary astrocytic astrocytoma</u></strong>-<em><strong>Anti-GFAP</strong></em>}}
• Pilocystic Astrocytoma-Children (benign)
  
  • Cystic mass w/mural nodule in cerebellum
  • _Other-_3rd vent or optic nerve
• Histo: Rosenthal fibers (eosinophilic)
• Found in Cerebellum good prognosis w/removal

Question 3

Glioblastoma Multiforme (astrocyte)

Answer 3

• Common in adults & very agressive (cortex)
  
  • Crosses corpus collosum (midline)
• **Seizures w/motor weakness **
• Area of necrosis-area of malignancy
  
  • Neoplastic cells surround it _{^{(pseudo-palasading)}}
  • Can be seen in MRI
  • High mitotic index
  • HIgh vascular proliferation

Question 4

Signs/Symptoms of Brain tumors

Answer 4

• Mass effect-Compression of BV & herniation
• Edema by herniation/masseffect
• Raised intracranial pressure-Headache
• Focal abnormality-Seizures
• Prognosis & Treatment depend on:
  
  • Location, histo grade, Age (adults worse)

Question 5

Oligodendroglioma

Answer 5

• Malignant well circumscribed w/cystic areas
• Focal calcification in white matter-frontal lobe
  
  • Low frequency of occurence (5%)
• X-ray-Calcification
  
  • Craniophryngioma _{^{(derived from Ratheke’s pouch)}}
    
    • _{^{Bi-temporal heminopsia (children)}}
  • Toxoplasma (Cat scratch)
  • Cytomeglovirus (HPV)
• Histo: Tumor cells cluster around neurons
  
  • “Fried egg appearance”

Question 6

Ependymoma

Answer 6

• Occurence @ any age most common in 1st 20 yrs
  
  • Commonly seen in children
• Ventricle-Reveals TRUE rosette pattern
  
  • Histo: _{^{Cells arranged around central vascular space}}
• Myxopapillary-Filum terminale of spinal cord _{^{(cauda equina)}}
  
  • Histo: Myxoid connective tissue core
• Clinical-Intracranial/ventricle=Hydrocephalous
  
  • Tumor cells seen in CSF

Question 7

Medulloblastoma

Answer 7

• Primitive neuroepi neoplasm-malignant children
• Lesion in cerebellum-Midline vermis=Children
  
  • _{^{Spreads through CSF-Drop metastasis through spinal cord}}
• Histo-Homer-Wright rosettes
• Treatment:
  
  • Radiotherapy entire spinal cord=70% _{^{(5 year survival)}}

Question 8

Meningioma

Answer 8

• Benign tumor from meningothelial cells (Arachnoid)
  
  • Round mass attached to dura
• Adult Female Pt-_{^{Tumor has estrogen receptors}}
• Slow growth=**Increase intracranial pressure **
  
  • _{^{<strong>Weakness of limbs & seizures</strong>}}
• Histo-
• Spindle cells in syncytial mass _^(whorls)
• Psammoma body-Ca+2 _{<strong>^{(papillary carcinoma of thyroid)}</strong>}
• Presents w/Neurofibromatosis:
• Type 1-_{^{Neurofibroma, <u>peripheral schwanoma</u>, pigmented skin & iris}}
• Type 2-_{^{schwanoma of CN8 <u>(hearing loss)</u>, post lens opacification}}

Question 9

Acoustic Neuromas/Schwannoma

Answer 9

• Benign neuroma of CN 8
  
  • S-100 ++ stain
• Presents @ Cerebellopontine angle
• Clinical-Hearing loss
  
  • Seen NF type 2
• Histo:
  
  • Antoni A = Verocay bodies
  • Antoni B-Low cellularity

Question 10

Metastatic tumor

Answer 10

• Border of grey & white matter follows MCA
  
  • _{^{Other location meninges}}
• Multiple well circumscribed 1-3 cm lesions
• Lung is primary site of origin
  
  • _{^{Others Acute lymphoblastic leukemia (cancer of WBCs)}}
  • Melanoma
• Meningeal metastasis-_{^{Leptomeningeal carcinoma}}
  
  • Malignant cells spread from leptomeninges
  • Breast cancer primary site