Tumours of the CNS

Question 1

what are the most common CNS tumours

Answer 1

gliomas, meningiomas

Question 2

what is the occurrence distribution of tumours of the nervous system

Answer 2

age distribution is bimodal

Adults: cerebrum, glioma and menigioma.

Question 3

where are tumours commonly found in children in the cerebrum or cerebellum

Answer 3

cerbellum (PNET and medullablastoma)

Question 4

where are tumours commonly found in adults in the cerebrum or cerebellum

Answer 4

Glioma and Meningioma

Question 5

do males have a increased risk of glioma or meningioma

Answer 5

glioma

Question 6

do females have an increased risk of glioma and meningioma

Answer 6

meningioma

Question 7

are neuronal tumours common or rare

Answer 7

rare

Question 8

Do neurones communicate with the blood supply

Answer 8

no

Question 9

how many astrocytes are there per neurone

Answer 9

10 astrocytes

Question 10

define astrocyte

Answer 10

support and protect

connect neurones with blood supply so that they can access the metabolites they need to function.

Question 11

define oligodendrocyte

Answer 11

myelin- insulate neurones

Question 12

define ependymal cells and choroid plexus cells (CSF)

Answer 12

produce CSF
protect brain from trauma
control external environment

Question 13

define micoglia defense

Answer 13

comes from bone arrow

sends astrocytes signal so that inflammatory cells can enter the blood brain barrier.

Question 14

what are the 4 types of glial cells (support cells)

Answer 14

astrocytes
oligodendrocytes
ependymal cells and choroid plexus
micoglial cells (defense)

Question 15

what is tumour of the neurone known as

Answer 15

ganglioma

Question 16

what is tumour of the glial cells known as

Answer 16

glioma

Question 17

what is tumour of the meninges known as

Answer 17

meningioma

Question 18

how many layers is the cerebrum

Answer 18

6 layers

Question 19

how many layers is the cerebellum

Answer 19

3 layers

Question 20

how are CNS tumours diagnosed

Answer 20

Histology- name of tumour

biological behaviour- grade of the tumour.

Question 21

do you have micoglial tumours

Answer 21

No

Question 22

what are the characteristic features of a benign tumour

Answer 22

slow growing
respect surrounding tissue
no/ slow progression
no recurrence
surgery -depends on postion

Question 23

what are the characteristic features of a malignant tumour

Answer 23

rapid growing
invade and destroy surrounding tissue
progress
recurrent
surgery and adjuvant therapy (radiotherapy and chemotherapy)

Question 24

what grade are benign tumours

Answer 24

grade 1

Question 25

are all graded tumours malignant

Answer 25

No | grade one can be benign.

Question 26

what histological changes are present in a malignant tumour

Answer 26

cell size and shape mitotic activity Necrosis-TNF to kill other cells vascular proliferation- increase endothelial cells to supply tumour.

Question 27

what are the 3 types of gliomas

Answer 27

Astrocytic tumours Oligodendroglioma Ependymoma

Question 28

what are the 2 types of nerve sheath tumours

Answer 28

Schwannoma and neurofibroma

Question 29

Microscopical features of astrocytic tumours

Answer 29

Fine fibrillary and microcystic background Increased cellular density Pleomorphism ( variation in size, shape and chromasia)

Question 30

what are the features of diffuse astrocytoma II

Answer 30

infiltrative, micro cystic fibrillary, low cellular density mild atypia no mitotic activity- grade 2

Question 31

what are the features of Anaplastic astrocytoma III

Answer 31

Moderate cellular density Moderate Pleomorphism Mitoses - grade 3

Question 32

what are the features of glioblastoma

Answer 32

High cellular density and mitoses Vascular proliferation Necrosis Histology- necrosis occurring in the centre and tumour cells are trying to escape

Question 33

is the men age for developing glioblastma younger or older than anapaestic astrocytoma

Answer 33

older

Question 34

what are the features of pilocytic astrocytoma

Answer 34

``` Children, cerebellum Well-defined, cystic Pilocytes Rosenthal fibres Vascular proliferation ```

Question 35

what are the features of oligodendroglioma II/III

Answer 35

Round uniform nuclei with clear cytoplasm (fried-egg appearance) Arborising capillaries (chicken wire) Calcifications

Question 36

what are the main features of Ependymoma II / III

Answer 36

Well-defined tumour, ventricles Pseudorosettes Round small uniform cells

Question 37

what are the main features on meningioma

Answer 37

Females, dura, adults Well-defined extra-axial tumour Whorls, psammoma bodies Histology- tumour cells whirl around each other.

Question 38

what are the main features of PNET

Answer 38

``` Children, cerebellum Very high cellular density- no cytoplasm seen in histology. Anaplastic hyperchromatic cells Frequent mitoses and apoptosis Rosette formation ```

Question 39

what are the main features of

Answer 39

``` Spindle-cell tumours Schwannoma I – 8th cranial nerve – Biphasic pattern: loose and dense areas – Reticulin rich Neurofibroma I – Spinal nerves – Rich in collagen ```

Question 40

what causes meningioma

Answer 40

radiotherapy

Question 41

what causes lymphoma

Answer 41

immunosupression

Question 42

what causes familial syndromes

Answer 42

NF1, NF2

Question 43

Mutations in any of Wnt 7, SHH and notch leads to what

Answer 43

tumours.

Question 44

MGMT promoter methylation is a predictive marker of which type of CNS tumour to akylating chemotherapy

Answer 44

glioblastomas

Question 45

1p/19q deletion is a predicative marker of n prognosis of what CNS tumour is patients receiving adjuvant radio and/ or chemotherapy.

Answer 45

(oligodendro)glial tumor

Question 46

What CNS tumours are IDH1/IDH2 mutations a diagnostic marker for

Answer 46

II and III gliomas as well as secondary glioblastomas

Question 47

What CNS tumours use BRAF duplication/fusion to determine the diagnosis of tumours.

Answer 47

Diagnostic marker for pilocytic astrocytomas, helpful to distinguish these from diffuse astrocytomas