Pathology of the CNS

Question 1

74 year old male presents with several month Hx of headaches

No fevers, neurological symptoms

O/E: no focal loss on neurological examination, no scalp tenderness or papilloedema

Ix?

Answer 1

MRI

Question 2

74 year old male presents with several month Hx of headaches

Findings on his MRI?

Answer 2

Area of high T2 signal in L superior frontal gyrus, abutting the falx, 3.2 x 4.9 cm extending inferiorly into L corona radiata

Mass effect with cortical expansion and mild inferior displacement and effacement of the body of the L lateral ventricle

Question 3

What are the most common primary brain tumours in adults?

Answer 3

Giomas (astrocytomas, etc)

Meningiomas

Acoustic nerve schwannomas

Pituitary adenomas

Ependymomas

Question 4

What kind of primary brain tumours are seen in children?

Answer 4

70% are infratentorial (in cerebellum, around 4th ventricle and brainstem)

More embryonal tumours, pilocytic astrocytma

Rarely: pituitary adenoma, metastases, meningioma, acoustic schwannoma

Question 5

Distinguish between diagnostic, prognostic and predictive biomarkers

Answer 5

Dx: help classify tumours with ambiguous histological features or allow for clinically useful subdivision within a histological tumour type

Prognostic: correlate with disease-free and overall survival

Predictive: provide data on response to a given therapy, allowing stratification into distinct therapeutic groups

Question 6

Give 5 examples of molecular markers seen in gliomas and state whether each is a diagnostic, prognostic or predictive biomarker

Answer 6

1p19q codeletion: predictive and prognostic for oligodendroglial tumours

IDH1/IDH2 mutations: prognostic in gliomas

MGMT promoter methylation: prognostic and predictive of response of glioblastoma to temozolamide

EGFR aberrations

BRAF duplications/fusions/mutations

Question 7

Female, 78, referred for Ix of impaired memory; has experienced several years of forgetting things like keys, etc

Now had an episode of being found in the shopping centre and unable to find her way home; memory loss predominant with insidious slow onset

No PHx of movement disorder, stroke-like episodes, frontal lobe symptoms of disinhibition, semantic or word-finding problems

O/E: orientated to time/place/person, no fever

Initial Ix including FBE, UEC, glucose, LFTs, CMP, TFTs, folate/B12 were all normal

An MRI was ordered

What does it show?