CNS tumours

Question 1

Are primary or secondary CNS tumours more common?

Answer 1

Secondary (mets) more common

Primary tumours children > adults

Question 2

WHO tumour grading

Grades I-IV

Answer 2

Grade I - Benign (long term survival)
Grade II - Death in >5y
Grade III - Death in <5y
Grade IV - Death in <1y
I and II low grade, III and IV high grade
Not all tumour types have all 4 grades

Question 3

Factors used to grade brain tumours

Answer 3

Cellularity
Mitotic activity
Necrosis
Endothelial proliferation (neoangiogenesis)
Molecular markers

Question 4

17q11
AD
Neurofibroma, pilocytic astrocytoma

Answer 4

NF1

Question 5

22q12
AD
Schwannoma, meningioma

Answer 5

NF2

Question 6

Most common primary tumour

Answer 6

Astrocytoma

Question 7

Most common primaries in secondary brain tumours

Answer 7

Small cell lung cancer
Breast
Malignant melanoma

Question 8

Ventricular tumour

Hydrocephalus

Answer 8

Ependymoma

Question 9

Focal deficit
Seizures
Personality changes

Answer 9

Supratentorial symptoms

Question 10

Cerebellar ataxia

Cranial nerve palsies

Answer 10

Infratentorial symptoms

Question 11

Tumours of oligodendrocytes + astrocytes (GLIAL cells)

Answer 11

Gliomas

Question 12

Most common primary tumours
Glioma - astrocytes
Peripheral - cerebral hemispheres
IDH1/2 good prognosis
Eventually become GBM
20-40yo

Answer 12

Diffuse astrocytoma

Diffusely common

Question 13

Malignant astrocytoma
Glial - astrocytes
Poorly delineated grey-pink tumours with central yellow necrosis
90% de novo, 10% from diffuse astrocytoma
Pseudo-palisading pattern
>50
Heterogenous 
Grade IV only

Answer 13

Glioblastoma (GBM)

God its bloody malignant

Question 14

Glial - oligodendrocytes
Slow growing
IDH1/2 co-deletion 1p/19q
Seizures often initial symptom
Small round nuclei surrounded by halos of clear cytoplasm (fried eggs)
Fine network of branching chicken wire capillaries
Calcification

Answer 14

Oligodendroglioma

Think: oligo - oil - fried eggs - clear cytoplasm, chicken wire capillaries, calcification, clonic seizures

Question 15

Slow growing and benign
Nests of cells (wave in ocean)
Psammoma body calcifications
Female >40

Answer 15

Meningioma

Men in nests of cells on waves, accompanied by Psammoma bodies

Question 16

Wet keratin appearance
Very slow growing and benign
Cysts of oily fluid + cells

Answer 16

Craniopharyngioma

Cranes sit on wet keratin to avoid the oily cysts

Question 17

Glial - astrocytes
Indolent childhood tumour
BRAF mutation
NF1
Cysts, Rosenthal fibres + granular bodies
Piloid hairy cells

Answer 17

Pilocytic astrocytoma

Children staring at hairy stars so they are ok

Question 18

Glioblastoma (GBM)
Meningioma
Oligodendroglioma
Craniopharyngoma

Answer 18

Supratentorial

Question 19

Medulloblastoma
Pilocytic astrocytoma
Meningioma
Ependymoma

Answer 19

Infratentorial

Question 20

Most common tumour location in children

Answer 20

Infratentorial

Question 21

Most common malignant tumour in children
Cerebellum
Super aggressive - type IV only
‘Homer-Wright rosettes’ - dense tangles of of neurons + neuroglial cells surrounded by tumour cells
Drop metastasis to base of spine through CSF

Answer 21

Medulloblastoma

Children awarded medals + rosettes because it is so aggressive and can drop through CSF