CNS tumours (9) Flashcards
What percentage are CNS tumours of all neoplasms?
2%
What’s the most common cancer in children?
Leukaemia, then CNS tumours
Which CNS tumours are most common in women?
Meningioma
Which CNS tumours are most common in men?
Glioma
What CNS tumours are most common in children?
Cerebellum, PNET (medulloblastoma)
Which CNS tumours are most common in adults?
Cerebrum, glioma and meningioma
Function of arachnoid membrane and pia mater
Protein and support
Tumour of arachnoid membrane and pia mater
Meningioma
Function of neurons
Sit in cortex, cause epilepsy, not in contact with blood supply need quiet environment, don’t give origin to many tumours, metabolic needs supplied by glia cells
Tumour of neuronal
Neurocytoma
Tumour of nerve sheath
Schwannoma
Glia cells
Astrocytes, Oligodendrocytes, Ependymal cells and choroid plexus cells, microglia
Tumour of glia
Glioma
Function of astrocytes
Support and protect (connect neurons with blood supply)
Tumour of astrocytes
Astrocytoma
Function of oligodendrocytes
Myelination
Tumours of oligodendrocytes
Oligodendroglioma
Function of ependymal cells
Controls, produces and moves CSF
Tumour of ependymal cells
Ependyoma
Function of choroid plexus cells
Specialised ependymal cell
Function of microglia
Defence (activated if ischaemia, allows inflammatory cells cross BBB)
Benign behaviour
Slow growing, respect surrounding tissue, no/slow progression, no recurrence, surgery
Malignant behaviour
Rapid growing, invade and destroy surrounding tissue, progress, recurrent, surgery and adjuvant therapy
Grade 1
Benign, no recurrence, no/very slow progression
Grade 2
Low grade, progression (astrocytoma 6-7 y)
Grade 3
High grade, rapid progression (astrocytoma 2-3 y)
Grade 4
Aggressive (necrosis and vascular proliferation)
Histological criteria for malignancy
- Cellular density and atypia
- Mitotic activity
- Necrosis
- Vascular proflieration
Atypia
Structural abnormality in cell
Hardest part about treating Gliomas?
Cells migrate through brain, can’t see borders/take it out completely, no barriers in communication
Space occupying lesion
Only 50ml allowed to accumulated, malignancy, abscess, haematoma
Astrocytic tumours
Fine fibrillary and microcytic background, increased cellular density, pleomorphism (size/shape/chromasia)
Diffuse astrocytoma II
Infiltrative, microcytic, fibrillary, low cellular density, mild atypia, no mitotic activity
Anaplastic astrocytoma III
Moderate cellular density, moderate pleomorphism, mitoses
Glioblastoma IV
High cellular density and mitoses, necrosis, vascular proliferation
Pilocytic astrocytoma I
Benign, non-infiltrative, children, cerebellum, well-defined, cystic, pilocytes (thin hair-like), Rosenthal fibres (think elongated worm-like), vascular proliferation
Oligodendroglioma II/III
Round uniform nuclei with clear cytoplasm (fried-egg appearance), arborising capillaries (chicken wire), calcifications
Ependymoma II/III
Well-defined tumour, ventricles, pseudo rosettes, round small uniform cells
Meningioma I
(Can be grade 2/3 aggressive), females, dura, adults, well-defined extra-axial tumour, whorls/swirls, psammonma bodies (lamellate calcified structures)
PNET (medulloblastoma) IV
Children, cerebellum, very high cellular density, anaplastic hyper chromatic cells, frequent mitoses and apoptosis, rosette formation
Nerve sheath tumours - Spindle-cell tumours
Benign
Nerve sheath tumours - Schwannoma I
8th cranial nerve, biphasic pattern (loose and dense areas), Reticulin
Nerve sheath tumours - Neurofibroma I
Spinal nerves, rich in collagen
Aetiology
Radiotherapy - meningioma
Immunosuppression - lymphoma
Familial syndromes - NF1, NF2
Stem cell pathways - Wnt signalling
Haematopoietic, epidermal, gut self-renewal > colon carcinoma/epidermal tumours
Stem cell pathways - Shh
Haematopoietic, neural, germ line self-renewal > medulloblastoma, basal cell carcinoma
Stem cell pathways - Notch
Haematopoietic, neural, germ line > Leukaemia, mammary tumours
4 markers of molecular diagnostics of gliomas
- MGMT promotor methylation
- 1p/19q deletion
- IDH1/IDH2 mutation
- BRAF duplication/fusion
Prognosis
Glioblastoma IV -
Factors affecting prognosis
Age, site, surgical resection, adjuvant therapy, genetic