Nervous System Tumours Flashcards
1
Q
Describe medulloblastoma
A
- Embryonal tumour
- Grade IV malignant tumour (high grade)
- Arises from external granular layer in the cerebellum
- On histology: small round blue cells, homer wright rosettes, mitotically active
- Located in the cerebellum
- Can metastasis in the CNS
- Well circumscribed
2
Q
List gliomas
A
Astrocytomas
- Pliocytic
- Diffuse
- Anaplastic
- Glioblastoma
Oligodendromas
Ependymomas
3
Q
List meningeal tumours
A
Meningiomas
4
Q
List peripheral tumours
A
- Neurofibromas
- Schwannomas
5
Q
Describe pilocytic astocytomas
A
- Grade 1
- Prominant in children
- Solid nodule with a cystic component on imaging
- Common in the cerebellum, hypothlamus, optic nerve
- Well circumscribed
- Rosenthal fibres, eosinophilic granular bodies on histology
- BRAF mutation
6
Q
Diffuse astrocytomas and anaplastic astrocytoma
A
Diffuse - Grade II - Diffuse - Most common in cerebral hemispheres - On histo hypercellular No 1p19p codeletion - Operation recommended before it becomes malignant
Anaplastic
- Grade III
- Diffuse
- Cerebral hemispheres
- Hypercellular, increased mitotic activity
- No 1p19p codeletion
7
Q
Describe glioblastoma
A
- Grade IV malignant tumour
- Diffuse, infiltrative mass
- Cerebral hemispheres
- Ring enhancement on imaging, internal necrosis
- Histo: hypercellular, increased mitotic activity, microvascular proliferation, necrotizing, pseudopalisading
- EGFR and PTEN mutations
8
Q
Describe oligodendrogliomas
A
- Grade II-III
- Cerebral hemispheres
- Histo: hypercellular, perinuclear halo (fried egg), negative for astrocyte markers
- 1p19q co deletions
9
Q
Describe ependymomas
A
- Grade II-II malignant tumour
- Common in cerebellum and spinal cord
- Well circumscribed (non-diffuse)
- Can drop metastases to seed the CSF
- Histo: perivascular and ependymal rosettes
10
Q
Describe meningiomas
A
- Grade 1
- Adults
- More common in females (possible due to progesterone/oestrogen receptors)
- Dural tails, extra axial location
- Can invade bone and brain
- Histo: cellular whorls, psammoma bodies (calcium deposits)
11
Q
Describe neurofibromas
A
- Neurofibromatosis type 1 (cafe au lait spots, lisch nodules in the eye)
- Histo: shredded carrot appearance of collagen strands
12
Q
Describe schwannomas
A
- NF2 association
- Histo: verocay bodies (palisading cells surrounding an acellular zone), biphasic neoplasm with antoni A (hypercellular) and antoni B (hypocellular) regions
- Common: vestibular schwannoma (aka. acoustic neuroma) from CN VIII. Causes hearing problems and disequillibrium
13
Q
Brain tumours: incidence, survival and aetiology
A
- Malignant tumours 2% of all cancers in adults
- 4400 newly diagnosed each year
- Overall incidence 7 per 100000 population
- 86% gliomas
- Highest rates in developed countries
- Most common over 30, drops at age 72
- 1.5:1 male to female ratio
- Women are more likely to get meningiomas
- Increasing incidence over time
- Survival dependent on age, histologic subtype and grade. Has improved over the past 30 years, but only 30% survive 1 year in 1986-90
- More affluent area=more lively to survive
- 13% five year survival in men and 16% in women in the UK, lower than US
- Second most commoncancer in children, 15-25% childhood malignancies
- Survival for children in UK has increased by 16% since 1971, and is higher than adults (59%)
- Risk factors: genetics (NF for example), ionising radiation, mobile phones (NOT A RISK), low frequency magnetic fields (NOT A RISK), immune factors (viruses, allergies, infections (WEAK), chemicals (n-nitroso compounds? Aspartame? tobacco smoke?), head trauma (recall bias?)
14
Q
Describe neuroimaging used in brain malignancy
A
- CT scan (used to quickly see what is going on - quick)
- MRI/fMRI
- MR spectroscopy (secondary)
- PET-SCAN (research)
Allows you to:
- Assess tumour type
- Guide resection
- Guide biopsies
- Assess response to treatment
- Assess recurrences
15
Q
Describe treatment of brain tumour
A
Targeted on the specific case:
- Watch and wait – Incidentally found tumours, benign appearances
- Surgery (stereotactic biopsy in inoperable tumours, open biopsy in inoperable but approachable tumours, and craniotomy for debulking)
- Radiotherapy
- Chemotherapy
- Combination of all of the above – Malignant tumours
