Histopathology 14 - Neuro-oncology

Question 1

Which 3 types of cancer are most likely to metastasise to the brain?

Answer 1

Lung
Breast
Malignant melanoma

Question 2

What is the most common form of primary brain tumour?

Answer 2

Astrocytoma

Question 3

Which genetic syndrome is associated with meningioma?

Answer 3

Neurofibromatosis type 2

Question 4

What type of tumour is being described by “a ventricular tumour that presents with hydrocephalus”?

Answer 4

Ependyoma

Question 5

Which brain tumour is an indolent CNS tumour of childhood?

Answer 5

Pilocystic astrocytoma

Question 6

Which type of brain tumour is soft, gelatinous and can become calcified?

Answer 6

Oligodendroma

Question 7

Which CNS tumour does Von Hippel-Lindau predispose to?

Answer 7

Hemangioblastoma

Question 8

Which CNS tumour does tuberous sclerosis predispose to?

Answer 8

Giant cell astrocytoma

Question 9

Recall the order in which imaging should be performed in CNS tumour investigation

Answer 9

1. CT
2. MRI (T1 and without contrast)
3. MR spectroscopy for gliomas (useful prognostically)

Question 10

Recall the 4 factors that guide grading of brain tumours

Answer 10

Morphology
Proliferative activity
Cell differentiation
Necrosis

Question 11

Recall the survival prediction for each grade of CNS tuour

Answer 11

Grade 1 = longterm
Grade 2 = >5 years
Grade 3 = <5 years
Grade 4 = <1 year

Question 12

What are the 2 broad subtypes of glial tumours, and in which age groups are they typically seen?

Answer 12

Diffuse (adults) or circumscribed (children)

Question 13

What grade are circumscribed glial tumours?

Answer 13

1 or 2

Question 14

What is the most common type of circumscribed glial tumour?

Answer 14

Pilocystic adenoma

Question 15

Mutation of which gene is associated with circumscribed glial tumours?

Answer 15

BRAF gene mutation

Question 16

Describe the progression of all diffuse glial cell tumours

Answer 16

Cannot be removed surgically, so all progress to glioblastoma within 10 years

Question 17

Which gene mutation is associated with diffuse glial cell tumour prediliction?

Answer 17

IDH gene

Question 18

How can glioblastoma and diffuse astrocytoma be differentiated on CT?

Answer 18

Glioblastoma = enhancing

Diffuse astrocytoma = non-enhancing

Question 19

Which gene mutation is always seen in oligodendroglioma?

Answer 19

IDH gene

Question 20

What is the WHO grade of oligodendroglioma?

Answer 20

Stage 2 - 3

Question 21

What is the pathognemonic histological finding in oligodendroglioma?

Answer 21

Fried egg cells

Question 22

How is oligodendroglioma most often managed?

Answer 22

Usually appropriate for surgical excision as often well-circumscribed

Question 23

What must be investigated in the case of multiple meningiomas?

Answer 23

Neurofibromatosis type 2

Question 24

What is the most important factor to assess when grading meningiomas?

Answer 24

Mitotic activity

Question 25

What is the most common type of embryonal CNS tumour?

Answer 25

Medulloblastoma

Question 26

Where do medulloblastomas always form?

Answer 26

In cerebellum near 4th ventricle

Question 27

What is the pathognemonic histological finding in medulloblastoma?

Answer 27

Very poorly differentiated ‘small round blue cells’

Question 28

Which subtype of medulloblastoma has the best prognosis?

Answer 28

WNT-activated subtype

Question 29

What is the basis of epigenetic profiling in CNS tumours?

Answer 29

DNA methylation of CpG islands