Histopathology 14 - Neuro-oncology Flashcards
Which 3 types of cancer are most likely to metastasise to the brain?
Lung
Breast
Malignant melanoma
What is the most common form of primary brain tumour?
What is the spectrum?
Astrocytoma
Ranges from pilocytic astrocytoma –> glioblastoma multiforme
Which genetic syndrome is associated with meningioma?
Neurofibromatosis type 2
What type of tumour is being described by “a ventricular tumour that presents with hydrocephalus”?
Ependyoma
Which brain tumour is an indolent CNS tumour of childhood?
Pilocystic astrocytoma
Which type of brain tumour is soft, gelatinous and can become calcified?
Oligodendroma
Which CNS tumour does Von Hippel-Lindau predispose to?
Hemangioblastoma
Which CNS tumour does tuberous sclerosis predispose to?
Giant cell astrocytoma
Recall the order in which imaging should be performed in CNS tumour investigation
- CT
- MRI (T1 and without contrast)
- MR spectroscopy for gliomas (useful prognostically)
Recall the 4 factors that guide grading of brain tumours
Morphology
Proliferative activity
Cell differentiation
Necrosis
Recall the survival prediction for each grade of CNS tuour
Grade 1 = longterm
Grade 2 = >5 years
Grade 3 = <5 years
Grade 4 = <1 year
What are the 2 broad subtypes of glial tumours, and in which age groups are they typically seen?
Diffuse (adults) or circumscribed (children)
Grades 1+2= circumscribed
Grades 3 + 4 = diffuse
What grade are circumscribed glial tumours?
1 or 2
What is the most common type of circumscribed glial tumour?
pilocytic astrocytoma
Mutation of which gene is associated with circumscribed glial tumours?
BRAF gene mutation
Describe the progression of all diffuse glial cell tumours
Cannot be removed surgically, so all progress to glioblastoma within 10 years
Which gene mutation is associated with diffuse glial cell tumour prediliction?
IDH gene
**this is a positive prognostic factor**
How can glioblastoma and diffuse astrocytoma be differentiated on CT?
Glioblastoma = enhancing
Diffuse astrocytoma = non-enhancing
enhancing aka more visible
the more aggressive tumour would be more visivle
Which gene mutation is always seen in oligodendroglioma?
IDH gene
What is the WHO grade of oligodendroglioma?
grade 2 - 3
What is the pathognemonic histological finding in oligodendroglioma?
Fried egg cells
How is oligodendroglioma most often managed?
Usually appropriate for surgical excision as often well-circumscribed
What must be investigated in the case of multiple meningiomas?
Neurofibromatosis type 2
What is the most important factor to assess when grading meningiomas?
Mitotic activity
What is the most common type of embryonal CNS tumour?
Medulloblastoma
Where do medulloblastomas always form?
In cerebellum near 4th ventricle
What is the pathognemonic histological finding in medulloblastoma?
Very poorly differentiated ‘small round blue cells’
Which subtype of medulloblastoma has the best prognosis?
WNT-activated subtype
W FOR WINNING
What is the basis of epigenetic profiling in CNS tumours?
DNA methylation of CpG islands
Which type of tumour is assoictaed with NF2?
Meningioma
Ventricular tumour, hydrocephalus
Ependymoma
Indolent childhood tumour
Pilocytic astrocytoma
Soft, gelatinous, calcified
oligodendroglioma
NF1 brain tumour
Optic glioma
neurofibroma
astrocytoma
Whatis Li fraumeni syndrome?
astrocytoma, PNET; many other tumours too (sarcomas, breast cancer,
leukemia)
What is turcot syndrome?
glioblastoma multiforme, medulloblastoma, pineoblastoma
Most common tumour of the sellar region?
Pituitary adenoma
** not craniopharyngioma
Which tumours arise from neuroepithelial region?
Astrocytic tumours: astrocytoma*, glioblastoma
o Oligodendroglial tumours: oligodendroglioma
o Oligoastrocytic tumours: oligoastrocytoma
o Neuronal and mixed neuronal-glial tumours: ganglion cell tumours, cerebral
neurocytomas/Neuroblastoma
o Embryonal tumours: medulloblastoma, primitive neuroectodermal tumours (PNET)
o Other: pineal, ependymal, and choroid plexus tumours
2nd most common brain tumour in children
Medulloblastoma
Where do the most common tumours originate from?
Glial cells
What does tumour grade tell us?
Survival
Which mutation identifies the mutation diffuse astrocytic tumours with a better prognosis?
IDH mutation
What type of tumour is a medulloblastoma?
Embryonal tumour
most common glial cell of the cns
astrocytoma
