CNS Tumours

Question 1

List some presentations of CNS tumours.

Answer 1

Headaches, often with associated nausea, vomiting, worse when lying down, and personality or mood changes.
focal neurological defects, seizures, high intracranial pressure, raised prolactin.
High ICP can cause coning and sudden death.

Question 2

In WHO grading, what does AMEN stand for?

Answer 2

A: atypia
M: mitoses
E: endothelial proliferation (ie. of cells nearby, desmoplastic stroma)
N: necrosis (palisaded is high grade)
Other: cellularity, molecular aspects.

Question 3

Briefly describe grades 1-4 of astrocytomas according to WHO.

Answer 3

Atrocytomas typically found in cerebral hemispheres.
Grade 1: low proliferation, well circumscribed, possible curative resection, eosinophilic granular bodies. grade stable. E.g. pilocytic astrocytoma.
Grade 2: may recur post resection and be grade unstable, moderate cellularity. E.g diffuse or fibrillary astrocytoma
Grade 3: more aggressive recurrence, often require adjuvant therapy, increased cellularity, moderate cellular pleomorphism and mitosis.
Grade 4: aggressive, high proliferation, rapid growth, marked pleomorphism, microvascular proliferation, pseudopalisading necrosis, haemorrhage, usually fatal. E.g. glioblastoma multiforme.

Question 4

Where do oligodendrogliomas tend to be found and what is there microscopic appearance, cytogenetics, presentation and prognosis?

Answer 4

Olidodendrogliomas typically found in white matter of cerebral hemispheres, slow growing.
Microscopy: may see calcification, delicate ‘chicken wire’ vessels and ‘fried egg’ appearance to cells, with round nuclei and perinuclear halo.
Cytogenetics: 1p19q deletion
Presentation: years of neurological complaints, inc seizures.
Prognosis: survival 5-10 years with surgery, chemo and radiotherapy.

Question 5

Where do ependymomas tend to be found and what is their microscopic appearance, presentation, prognosis?

Answer 5

Ependymomas tend to be found in the lining of the ventricles, central canal and spinal cord. Tend to occur in the fourth ventricle in children and in the spinal cord in adults.
Microscopy: perivascular rosettes (try to make canals)
Presentation: symptoms related to CSF obstruction.
Prognosis: poor as easily disseminate in CSF.

Question 6

How does a choroid plexus papilloma present?

Answer 6

As hydrocephalus.

Question 7

List some types of neuronal tumours.

Answer 7

gangliocytoma, ganglioglioma, neurocytoma, medulloblastoma.

Question 8

Where do neurocytomas tend to be found and what is their microscopic appearance and prognosis?

Answer 8

Neurocytomas often present as intraventricular tumour or from the septum pellicidum.
Microscopy: small round uniform cells of neuronal lineage.
Prognosis: good unless dissemination via CSF.

Question 9

Where do medulloblastomas tend to be found and what is their microscopic appearance, presentation, and prognosis?

Answer 9

Medulloblastomas tend to be found at the vermis of the cerebellum.
Microscopy: hypercellular tumour with several mitosis and Homer Write rosettes (core of axons).
Presentation: ataxia, headache, CSF obstruction
Prognosis: poor, highly malignant but radiosensitive.

Question 10

Where do meningiomas tend to arise from and what is their microscopic appearance?

Answer 10

Meningiomas arise from meningothelial cells of arachnoid granulations. Slow growing, firm, rubbery appearance.
Microscopy: whorls of meningothelial cells, psammoma bodies and pearls of calcium.
Some may present as nasal polyp as grows down through cribiform plate.