High grade gliomas Flashcards

Question

What were grade 4 (IDH Mutant) astrocytomas labelled as prior to the WHO classification of CNS tumours 2021?

Answer 1

Considered Glioblastoma prior to the ‘WHO classification of CNS tumours -5th Ed (2021) Classification changed based on the presence of IDH mutation – Glioblastoma now considered separate entity.

Answer 2

Generally younger presentation than glioblastoma

Answer 3

M:F around 1.5

Answer 4

The same as glioblastoma

Answer 5

5 year survival – 3.6 yrs. – better than glioblastoma

Answer 6

Around 10% of pre-WHO 5th Ed of cases=G4 IDH Mutant (would have been classified as glioblastoma prior to this)

Answer 7

IDH-Wildtype

Answer 8

Any age but most common in those 70 +

Answer 9

Cerebrum Basal ganglia Rarely arises in the cerebellum A small percentage cross corpus callosum when it is described as the “butterfly tumour”

Answer 10

Macroscopic appearance – grey mass with areas of haemorrhaging, yellow necrosis and sometimes cysts. Appear to have a capsule – this is an artefact of rapidly growing tumour and compressed brain. Adjacent brain is swollen and oedematous Spreads along white matter tracts.. Migratory cells are found many cm from the main body of the tumour Tumour appears to be multi-focal but are actually from one site Microvascular proliferation and necrosis are the hallmarks of glioblastoma. Glioblastoma is recognisable radiologically

Answer 11

Most malignant form of glioma. It is poorly differentiated and highly invasive. It has areas of necrosis and microvascular proliferation Diffuse astrocytic tumour Necrosis Microvascular proliferation EGFR gene amplification Formed de novo.

Answer 12

Methylguanine DNA Methyltransferase

Answer 13

Generally longer survival than those without MGMT methylation promotion Positively impacts the efficacy of Temozolomide ?Offer temozolomide to patients without promotion

Answer 14

Patients whose tumours express IDH mutations have improved survival compared to wild-type IDH 90% Wild-Type Tumour formed as a Glioblastoma from the beginning 10% Mutated Tumour was previously a lower grade tumour

Answer 15

Isocitrate Dehydrogenase

Answer 16

Giant cell glioblastoma Gliosarcoma Epithelioid glioblastoma

Answer 17

Occurs in older people No prior history of tumour Poor prognosis

Answer 18

Grey masses Areas of haemorrhage Yellow necrosis Cysts Never encapsulated (appear to have capsule – this is an artefact of rapidly growing tumour and compressed brain) Tissue adjacent to tumour oedematous Oedema located around white matter Offers a route for satellite cells to migrate from the main body of the tumour This can make the tumour appear multifocal

Answer 19

Biopsy to confirm diagnosis Removal of maximum volume of tumour possible (maximal safe resection (MSR) Radiotherapy Chemotherapy (TMZ)

Answer 20

30-50 years old

Answer 21

Arise in white matter: Frontal, parietal and temporal lobes occasionally arises in the spinal cord Very rarely arises in the cerebellum

Answer 22

Slow growing Patient often describes long history of seizures. CT, MRI and Plain skull x-rays often reveal calcification (~50% cases) Long standing tumours may cross corpus callosum – even when low grade Unlike glioblastoma – occasionally high grade oligodendroglioma can do unaccountably well

Answer 23

Often areas of calcification evident

Answer 24

Yes – PVC (procarbazine, lomustine, vincristine)