Central Nervous System Pathology – Tumours, SOLs & Neurodegeneration

25 question-and-answer flashcards covering tumour classification, glioma features, grading, space-occupying lesions, Alzheimer’s and Parkinson’s disease for CNS pathology revision.

Into primary tumours (neuroglial, neuronal, poorly-differentiated) and secondary/metastatic tumours.

How are central nervous system (CNS) tumours broadly classified?

Astrocytoma, oligodendroglioma and ependymoma.

Which three tumour types are included under gliomas?

Medulloblastoma.

Which brain tumour is the most common malignant neoplasm in children after pilocytic astrocytoma?

Glial fibrillary acidic protein (GFAP).

What protein is a key immunohistochemical marker for astrocytes and astrocytic tumours?

Grade I (none of the four malignant features present).

Which tumour grade corresponds to a pilocytic astrocytoma in the WHO grading system?

Nuclear atypia, abnormal mitoses, endothelial cell proliferation and coagulative necrosis.

Name the four histologic features used to grade astrocytomas.

Pseudo-palisading necrosis.

What microscopic pattern is characterised by tumour cells lining necrotic areas in glioblastoma multiforme?

Oligodendroglioma.

Which glioma displays “fried-egg” cells with perinuclear halos and frequent calcification?

Ependymal cells lining the ventricles and spinal cord central canal.

From which cells do ependymomas arise?

Perivascular pseudorosette.

What type of rosette is classically seen in ependymoma?

Cancers of the lung, breast and skin (melanoma).

List three common primary cancers that metastasise to the brain.

Any growth within the skull that exerts pressure and compresses brain tissue.

Define a space-occupying lesion (SOL) in the brain.

Morning headache worsened by bending, nausea/vomiting and seizures (others include lethargy, paralysis, etc.).

Give three common clinical symptoms of intracranial space-occupying lesions.

Neocortex, hippocampus, amygdala and basal forebrain cholinergic system.

Which brain regions are most affected in Alzheimer’s disease?

Accumulation of Aβ-42 fragments from APP forms extracellular plaques that trigger neuronal death.

State the central premise of the Amyloid (BAPtist) hypothesis of Alzheimer’s disease.

Hyperphosphorylated tau forming neurofibrillary tangles.

What abnormal protein accumulation is highlighted by the Tauist hypothesis of Alzheimer’s disease?

Early (mild), Middle (moderate) and Late (severe) stages.

List the three general stages of Alzheimer’s disease progression.

Dopaminergic neurons of the substantia nigra pars compacta.

Which neurotransmitter-producing neurons are primarily lost in Parkinson’s disease?

Resting tremor, bradykinesia, muscular rigidity and postural instability.

Name four classic motor symptoms of Parkinson’s disease.

Lewy bodies composed mainly of misfolded α-synuclein.

What pathological intracytoplasmic inclusions are characteristic of Parkinson’s disease?

Examples: α-synuclein gene mutations, aging, environmental toxins, oxidative stress or mitochondrial dysfunction (any two).

Give two genetic or environmental factors implicated in Parkinson’s disease pathogenesis.

Approximately 20 %.

What percentage of all childhood cancers are tumours of the CNS?

Grade III; increased cellularity, nuclear atypia and mitoses but no necrosis or endothelial proliferation.

Which grade of astrocytoma is termed anaplastic astrocytoma and what distinguishes it?

About 15 months.

What is the median survival time for patients with glioblastoma multiforme?

WNT, SHH, Group 3 and Group 4.

Which molecular subgroups are included in the latest classification of medulloblastoma?