Tumors

Question 0

Diffuse Astrocytoma

Answer 0

• Grade II
• No mitosis
• Pleomorphic, angulated and hyperchromatic nucleus
• Pathology: diffusely invades cerebrum producing midline shift
• Gemistocytic variant: plump cells with pink cytoplasm

Question 1

List the diffuse, infiltrating astrocytomas

Answer 1

1. Diffuse Astrocytoma (Grade II)
2. Anaplastic Astrocytoma (Grade III)
3. Glioblastoma (Grade IV)

Question 2

Anaplastic Astrocytoma

Answer 2

-Grade III (mitosis)

Question 3

Glioblastoma

Answer 3

• Grade IV

- Necrosis, microvascular proliferation, glomeruloid tufts

Question 4

Glioblastoma genotypes

Answer 4

• Primary: older people, EGFR

- Secondary: younger people, P53, IDH1/IDH2 (better prognosis)

Question 5

What is the relatively circumscribed, non-infiltrating tumor we learned about?

Answer 5

Pilocytic Astrocytoma

Question 6

Pilocytic Astrocytoma

Answer 6

• Grade I (non-infiltrative, rarely progress, well circumscribed/easy to resect)
• 7q34 BRAF+ KIAA1549 novel fusion oncogene
• Children and young adults
• Cystic cerebellar lesion
• Rosenthal fibers

Question 7

Oligodendrogliomas

Answer 7

• Grade II
• Well differentiated, infiltrating tumor
• Expands into gyri and deep white matter
• Fried egg/chicken wire appearance (vessels branching capillaries)
• Loss of heterozygosity

Question 8

Embryonal Tumors

Answer 8

Medulloblastoma

Question 9

Medulloblastoma

Answer 9

• Grade IV embryonal tumor made from granule neurons
• Most commonly vermis–>4th ventricle
• Well circumscribed, gray/pink with small foci areas of necrosis and gelatinous opacification with CSF dissemination
• 40% have Homer-Wright Rosettes (rosette around neuropil)

Question 10

Ependymomas

Answer 10

• Grade II

- Pseudorosettes (neoplastic cells cluster around blood vessels)

Question 11

List the cranial/spinal nerve tumors

Answer 11

Schwannomas and Neurofibromas

Question 12

Schwannoma

Answer 12

• Slowly growing neoplasm
• CN VIII most commonly effected
• NF2 patients present with bilateral CN VIII involvement

Question 13

Neurofibromas

Answer 13

• Grade I
• 1. Dermal producing nodular lesion of skin or 2. Intraneural, solitary or plexiform
• If multiple=NF1
• incorporates axons, are harder to remove whereas schwannoma displaces normal elements of nerve to one side

Question 14

Meningioma

Answer 14

• Meningothelial cells of the leptomeninges
• F>M
• Occurs in 50% of pts with NF2
• Transitional meningioma=whorls and cords of neopastic cells
• Psammomatous meningioma=numerous compact whorls
• Fibrous=fibrous
• 15% of intracranial neoplasma are meningiomas

Question 15

Metastatic tumors

Answer 15

• Secondary CNS neoplasms account for 15%

- Most commonly from: Lungs, breast, skin, kidney and colon