CNS Tumours

Question 1

Diffuse glioma ususally have genetic alteration of ……..

Answer 1

Isocitrate dehydrogenase 1&2 enyzume

Question 2

Diffuse astrocytic tumors are most common in age……, and in site…..

Answer 2

4th through 6th decades of life
Cerebral hemispheres

Question 3

Mention the most common symptoms of diffuse astrocytic tumors

Answer 3

Seizures, headaches, focal neurologicl deficits related to anatomic site of involvemnet

Question 4

Describe groos picture of
1. Diffuse astrocytoma
2. Glioblastoma

Answer 4

1. Poorly defined, gray, infiltartive tumors that expand & distort the invaded brain tissue without forming dicrete mass, invasion beyond grossly visible border is always present, cut section may be firm or gelatinous, cystic degeneration may be present.
2. Some areas are firm & white, others are soft & yellow. Other regions show areas of cystic degeneration and hemorrhage.

Question 5

MRI feature of gliobalstoma is…..

Answer 5

Irregular rim-enhancing mass

Question 6

Describe microscopic features of diffuse astrocytic tumors

Answer 6

Diffuse astrocytoma: mild to mod increase in cellularity, nuclear pleomorphism, feltwork of glial fibrillary acidic protein-postive astrocytic cell processes that give the background a fibrillary appearnace
Anaplastic astrocytoma: more dense cellularity and have greater nuclear pleomorphism + mitoses
Glioblastoma: similar to prev as well as either necrosis (w/ pseudopallisading nuclei) Or vascular proleiferation.

Question 7

Mention the following with regards oligodendroglioma
1. Age
2. C/P
3. Site
4. Genetic mutation

Answer 7

1. 4th to 5th decades of life
2. Several years of antecedent neurologic complaints often including seizures
3. Cerebral hemispheres, frontal/ temporal lobes
4. Codeletion of chromosome 1p & 19q

Question 8

Mention microscopic features of:
1. Oligodendroglioma
2. Anaplastic oligodendrogioma

Answer 8

1. Sheets of regular cells with rounded nuclei containing fineky granukar chromatin surrounded by clear halo of cytoplasm, contains a delicate network if anastomosing capillaries, mitotic activity is low.
2. Higher cellularity, nuclear anaplasia, prominent mitotic activity, microvascular proliferation is prominent, may contain necrosis.

Question 9

Mention the following with regards pilocytic astrocytoma
1. Age
2. Site
3. Genetic mutation

Answer 9

1. Children & young adults
2. Cerebellum less commonly 3rd ven, optic pathway, spinal cord, cerebrum.
3. Activation of mitogen-activated protein kinase & inactivation of neurofibromatosis-1 gene

Question 10

Describe gross & microscopic picture of pilocytic astrocytoma

Answer 10

G, cystic, with a mural nodule in the wall of the cyst; if solid, it is usually well-circumscribed
M, low to mod cellularity, biphasic pattern with varying proportionsof compacted bipolar cells with Rosenthal fibers & loose-textured multipolar cells with microcysts. Eosinophilic granular bodies are more often encountered in the loose regions. Necrosis & mitoses are rare.

Question 11

Mention the following with regards oligodendroglioma
1. Age
2. Site
3. Genetic mutation

Answer 11

1. First 2 decades of life
2. Near 4th ven
3. NF2

Question 12

Describe G&M picture of ependymoma

Answer 12

G, well-circumscribed with gritty calcium deposits, flow through foramina of Luschka & Magendie to wrap around brain stem’s CNs and vessels this has been termed plastic ependymoma
M, uniform small cells in a fibrillary matrix ccc by perivascukar anucleate zones (pseudorosettes). Classified into classic & anaplastic histologic patterns

Question 13

GR: The practice of histologically grading epedymoma may soon become obsolete

Answer 13

Specific genetic alterations & molecular groups have been recently proposed as prognostic/predictive factors for there tumors as there is no association between grade and biological behaviour.

Question 14

Schwannomaa occurs in……..dec of life

Answer 14

4th to 6th

Question 15

……is the hallmark of NF2. ……IS THE MOST COMMON PRESENTATION OF SCHWANNOMATOSIS

Answer 15

Biltaeral vesticular tumors
Pain

Question 16

With respect to meningioma, it is more common in….., but higher grade lesions are more common in……

Answer 16

Females
Males

Question 17

…. Is the only established environmental risk factor for meningioma….. is suggested

Answer 17

Ionizing radiation
Hormones

Question 18

Meningioma occurs in 50% of people with inactivation of……in…..encoding…….

Answer 18

NF2
Ch22
Merlin tumor suppressor

Question 19

Meningioma may affect skull bone causing……or grow along wing of sphenoid forming…..

Answer 19

Hyerostosis
En plaque meningioma

Question 20

Enumerate microscopic pattterns of meningioma

Answer 20

Synctial, fibroblastic, transitional & psammomatous

Question 21

Mention criteria of atypical meningioma

Answer 21

3 of the following: inc cellularity, small cells with high N/C ratio, prominent nucleoli, sheeting, necrosis.

Question 22

CNS lymphoma in immunosuppressed is always +ve for….., incidence in after …….

Answer 22

Oncogenic Epstein-Barr virus
60 yrs

Question 23

Germ cell tumor occur in……

Answer 23

Midline commonly pineal gland (males) & suprasellar regions

Question 24

Germ cell tumor occurs in…..
The most common primary CNS getm tumor is…..& resembles……

Answer 24

First 2 decades of life
Germinoma-testicular seminoma

Question 25

Describe G&M picture of metastatic tumors in CNS

Answer 25

G, metastases form sharply demarcated masses & elicit edema
M, boundary between tumor & brain parenchyma is sharp with surrounding reactive gliosis

Question 26

Mode of inheritence of Von Hippel-Lindau disease

Answer 26

Autosomal dominant
Ch3p