CNS tumors

Question 1

What is the rate of primary and metastatic brain tumors

Answer 1

50% each

Question 2

What is the order of commonality of metastatic cancer sources

Answer 2

Lung, breast, skin (malignant melanoma), kidney, GI tract

Question 3

What are locations of tumors and what tumors are most common in adults and children

Answer 3

Adults: Supratentorial - glioblastoma multiforme (astrocytoma), meningioma, schwannomaChildren: Infratentorial - Pilocytic astrocytoma, medulloblastoma, ependymoma

Question 4

What is the most common and second most common brain primary tumor

Answer 4

Glioma most common (50%)Meningioma second most common (25%)

Question 5

Do brain tumors metastasize?

Answer 5

No, but they recur within brain a lot

Question 6

What are two major clinical features seen with brain tumors

Answer 6

1.) Increased ICP - headaches upon awakening or certain positions, NV in mornings, altered consciousness, papilledema, brain herniation2.) Focal deficits - cranial nerves, seizures, specific neurologic deficits, hyperfunctioning structure

Question 7

What is the imaging test of choice for CNS neoplasms and the definitive test to diagnose

Answer 7

1.) MRI2.) Brain biopsy - only definitive way to determine type

Question 8

For treatment of CNS neoplasms, which tumors can be surgically resected and which ones cannot

Answer 8

Resction - meningioma, pituitary adenoma, schwannomaNo resection - gliomas (astrocytomas and oligodendrogliomas)

Question 9

What should you do next for tumors that cannot be completely resected

Answer 9

Radiation therapy

Question 10

What is the role of chemotherapy in CNS neoplasms

Answer 10

Limited

Question 11

Besides treating tumor, how would you treat the increased ICP

Answer 11

Mannitol, hyperventilation, steroids

Question 12

What is a good classification of tumors based on location and malignancy

Answer 12

Intraparenchymal (malignant) - includes astrocytoma, oligodendroglioma, primary lymphoma, and metastatic brain tumorsExtraparenchymal (benign and resectable) - Meningioma, schwannoma

Question 13

Who is most likely to get a primary lymphoma

Answer 13

Immunosuppressed patients (transplant or AIDS)

Question 14

What is characteristically seen in patients with primary lymphoma on MRI and in the CSF

Answer 14

Solitary weakly ring enhancing periventricular lesion on MRI, and EBV DNA in CSF in HIV/transplant patient (Uworld)

Question 15

What are the two astrocytomas seen (adults and children)

Answer 15

Adults - glioblastoma multiformeChild - pilocytic astrocytoma

Question 16

Is glioblastoma multiforme malignant?

Answer 16

Yes, very

Question 17

What is the characteristic pattern of glioblastoma multiforme

Answer 17

Always arises in cerebral hemisphere, heterogeneous, crosses corpus callosum to form butterly lesion with centralized necrosis with pseudopallidating cells outside, GFAP positive

Question 18

What is the survival rate for glioblastoma multiforme

Answer 18

Poor, 90% die within 3 months

Question 19

What is a good treatment for glioblastoma multiforme

Answer 19

Surgery + radiation 2 cm margin + chemotherapy (temozolomide is agent of choice)

Question 20

What is oligodendroglioma

Answer 20

Another glioma (besides astrocytoma) that is malignant and intraparenchymal

Question 21

How does oligodendroglioma look on imaging and biopsy

Answer 21

Imaging: Calcified tumor in white matter, usually frontal lobe, may have seizuresBiopsy: Fried egg appearance

Question 22

How long do ologidendroglioma patients have?

Answer 22

10 to 15 years

Question 23

What are primary metastatic tumors

Answer 23

Tumors that metastatisize to the brain, most common are lung, breast, skin (melanoma), kidney, and GI tract

Question 24

What is the medical treatment for metastatic tumors

Answer 24

Phenytoin for seizure prophylaxisDexamethasone for cerebral edema, give with ranitidine

Question 25

What is the treatment for multiple brain metastases vs. just one

Answer 25

Multiple: WBRTLess than 3: Stereotactic radiosurgery (also if deep-rooted)Single: Surgical resection followed by radiation