Childhood brain tumours Flashcards
What are the 5 childhood brain tumours?
- Pilocytic astrocytoma
- Medulloblastoma
- Ependymoma
- Craniopharyngioma
- Pinealoma
What is the most common childhood brain tumour?
Pilocytic astrocytoma
Where are pilocytic astrocytomas found?
Posterior fossa (cerebellum)
- May be supratentorial
Describe pilocytic astrocytoma on histology
- Astrocye origin GFAP +ve
- Bipolar neoplastic cells with hair-like projection
- Associated with microcysts and Rosenthal fibers (eosinophilic corkscrew fibers)
What do pilocytic astrocytomas look like grossly?
Cystic + solid
What childhood tumour is GFAP +ve?
Pilocytic astrocytoma
What childhood brain tumours may compress the 4th ventricle causing hydrocephalus?
- Medulloblastoma
- Ependymoma
- Pinealoma is from cerebral aqueduct compression
What is the most common malignant brain tumour in children?
Where can the tumour metastasise to?
Medulloblastoma
- “Drop metastases” to spinal cord
What childhood brain tumour may cause hydrocephalus and truncal ataxia (cerebellar vermis affected)?
Medulloblastoma
What are the features of Medulloblastoma on histology?
Primitive ectodermal tumour
- Homer-Wright rosettes
- Small blue cells
- Synaptophysin +ve
Where are ependymomas most commonly found?
4th ventricle
Describe the histology of Ependymomas
- Perivascular pseudorosettes
- Rod-shaped blepharoplasts (basal ciliary bodies) found near nucleus
What is the most coomon childhood supratentorial tumour?
Craniopharyngioma
What childhood brain tumour is associated with bitemporal hemianopia?
Cranopharyngioma
What childhood brain tumour is derived from remnants of Rathke’s pouch (ectodrrm)?
Craniopharyngioma
Desribe the histology of Craniopharyngioma?
- Calcification
-Cholesterol crystals found in ‘motor oil’ like fluid within tumour
What are the 3 main symptoms of Pinealoma?
- Parinaud syndrome (compression of tectum -> vertical gaze palsy)
- Obstructive hydrocephalus (compression of cerebral aqueduct)
- Precorious puberty in males due to hCG production
What tumours are similar to pinealomas?
Similar to germ cell tumours (eg testicular seminomas)
How can pinealomas cause vertical gaze palsy?
Tumour compresses mesencephalic tectum, including the superior colliculus adjacent oculomotor (origin of cranial nerve III) and Edinger-Westphal nuclei, causing dysfunction to the motor function of the eye
Perivascular pseudorosettes and rod-shaped blepharoplasts are found near the nucleus are found in what tumour?
Ependymoma
Homer-Wright rosettes and small blue cells are found in what tumour?
Medulloblastomas
