TUMOURS OF THE CENTRAL

1
TUMOURS OF THE CENTRAL NERVOUS SYSTEM
FM Brett MD., FRCPath
2

• At the end of this lecture you
• should be able to
• Give basic classification of CNS tumours
• Understand how patients present
• Know the common tumours in children and adults
• Know what is meant by paraneoplastic syndromes
• Know that concept of benign and malignant
• meaningless when applied to CNS tumours

3

• CLASSIFICATION OF CNS TUMOURS
• Intrinsic tumours account for virtually all
  tumours in children and 60 of primary CNS
  tumours in adults
• Extrinsic tumours arising from cranial and
  spinal nerves and dura.
• Tumours arising from adjacent structures i.e
  pituitary gland and metastatic tumours.

4
The pathologist and CNS neoplasms Clinical
details of importance Age Sex F/X
Site of neoplasm
5
INCIDENCE Second commonest form of cancer in
children Accounts for 3.5 of all deaths in the
1-14 year age group Sixth commonest cause of
cancer deaths in adults 25 of all tumors in
adults are in the brain and 35 are
neurectodermal and 40 are metastatic
6
Most primary tumors are sporadic and of
unknown aetiology Secondary tumors vary
greatly between 14-40 Fewer than 5 are
associated with hereditary syndromes that
predispose to neoplasia
7
Heritable syndromes with increased risk of CNS
tumours
Syndrome Gene locus Gene Type of CNS tumour
NF type 1 17q11 NF1 Neurofibromameningioma, optic nerve glioma
NF2 22q12 NF2 Meningioma, schwannoma
TS 9q34,16p13 TSc1/TSC2 SEGA
VHL 3p35 VHL Haemangioblastoma
Li-Fraumani 17q13 p53 glioma
Gorlins syndrome 9q31 PNET
8
CNS neoplasms present with epilepsy (focal
or generalised) focal neurologic deficits
symptoms and signs of raised ICP symptoms and
signs of hydrocephalus
9
SSites of cerebral tumors
Sites of cerebral tumors ADULTS Supratentorial
tumors account for 90 Therefore increased
incidence of epilepsy and decreased incidence of
headache Posterior fossa tumours cause headache
and vomiting as early features
10
CHILDREN Cerebellum Pons Optic nerve/chiasm SUPRA
TENTORIAL TUMORS ARE RARE Therefore Headache,
vomiting, visual disturbances common Epilepsy -
unusual
11

• Diagnosis
• 1. Clinical picture
• 2. CT or MRI scan
• Biopsy
• smear
• Frozen section
• paraffin section

12
(No Transcript)
13

• Factors in the aetiology of CNS neoplasms
• 1. Sex gliomas commoner in males
• meningiomas commoner in females
• Exposure to ionizing radiation implicated
• in the genesis of
• meningiomas
• gliomas
• nerve sheath tumors
• Primary CNS lymphoma is associated with
• immunodeficiency
• Nitroso compounds cause CNS neoplasms in animals
• No convincing evidence has linked CNS neoplasms
  with trauma, occupation, diet, electromagnetic
  fields

14
Prognostic factors in CNS tumors Patient
characteristics Tumour characteristics
15
Patient characteristics Age General
physical characteristics Extent of surgical
resection
16
Tumour characteristics Specimen
procurement Phenotypic analysis
Proliferative capacity
17

• EFFECTS OF TUMOUR
• Local destruction of neural tissue
• Oedema
• Distortion of neural tissue
• Raised ICP

18
Grading of Gliomas (WHO) Grade 1 1V based on
presence of pleomorphism, mitoses, vascular
proliferation and necrosis Median Overall
Survival AA 3-5 years OS GBM 1
year Secondary GBM younger patients with
pre-existing lower grade glioma Primary 60-70
19

• Primary GBM
• high frequency of RGFR amplification
• p16 loss
• Secondary GBM TP53 mutations

20
Oligodendroglioma Concurrent deletion of 1p
and 19q In AO good response to DXT and
chemo Criteria for anaplasia nuclear
pleomorphism, mitotic activity, endothelial
vascular hyperplasia and necrosis For
anaplasia 2 features one of which frequent
mitoses or VEH
21
Predictive Markers in Malignant Gliomas 1p19q
loss in AO associated with enhanced
chemosensitivity and longer overall survival
MGMT status in GBM inc responsivness to
temezolamide EGFR inc in GBM
22
Prognosis Benign and malignant are
meaningless with respect to brain tumors. It
is the technical aspects that determine the
prognosis
23
(No Transcript)
24
Haemorrhage and midline shift
25
Raised ICP As neoplasm grows contents of
the skull are compressed Within the skull
brain occupies 1400mls CSF 100-200mls and blood
100-150mls Displacement of CSF and blood
compensate initially for mass effect Then ICP
rises quickly mass effect compression
vascular insufficiency
26
IC
ICP Herniations Subfalcine herniation
Tentorial herniation Tonsillar herniation
27
FALSE LOCALISING SIGNS Occulomotor nerve
compression Abducens nerve compressed
against the petrous ligament Ipsilateral
hemiparesis from compression of the cerebral
peduncle against the tentorium PCA infarction
from compression of the artery against the
tentorium
28
(No Transcript)
29
Under the age of 16, 75 occur In the posterior
fossa Pilocytic astrocytoma Ependymoma
Medulloblastoma
30
Medulloblastoma
Childhood Male predominance
31
Medulloblastoma seeding down the cord
32
Ependymoma childhood Often occur in areas
where complete surgical excision is impossible
33

• Neuroectodermal tumours
• Prognosis depends on
• Site
• histology

34
Meningiomas Older adults usually female
Increased incidence in Von Recklinhausen
disease Association between meningiomas and
breast cancer
35

• Meningioms
• Clinical presentation depends on
• Site
• Rapidity of growth
• Prognosis benign (usually)
• slowly growing
• often can be completely
• excised

36
Meningioma arising from the falx cerebri
37
(No Transcript)
38

• Spinal cord tumors
• Extradural metastatic carcinoma,
• myeloma, lymphoma
• Intradural (extramedullary) - meningioma
• schwannoma
• 3. Intramedullary - gliomas

39
Metastatic tumours in Adults Common Over
the age of 65 commonest variety of
intracerebral neoplasm Mets in children
uncommon but CNS well recognised site for relapse
of ALL
40
(No Transcript)
41
(No Transcript)
42
Case History Patient transferred with a
history of Headaches and drowsiness
Microcytic hypochromic anaemia,
Thrombocytopenia CT hydrocephalus no
known cause EVD inserted IVH RIP
43
(No Transcript)
44
E. O. N Admitted on 02/10/00 with stridor and
Personality change Progressive
deterioration Infective screen negative ? sCJD ?
?
45
Investigations CSF NAD MRI - ? EEG - NAD
46
(No Transcript)
47
(No Transcript)
48
(No Transcript)
49
(No Transcript)
50
(No Transcript)
51
PM A50/01 Paraneoplastic encephalomyelitis Tumou
r mass 8x6x4 cm, wt 120gms Anterior, inferior and
left lateral to the Thyroid
52
Paraneoplastic encephalomyelitis neurological
disorders of unknown cause associated with
systemic malignancy Subacute progressive
course over mths years May precede follow
or occur simultaneously with a systemic cancer
53

• Include
• Encephalitis
• Cerebellarr cortical degeneration
• Myopathy
• Peripheral neuropathy
• Necrotising myelopathy

54
AB Anti Yo Anti HU Anti Ri Anti CAR
Neurological synd Cerebellar deg Encephalo myelitis Opsoclonus-ataxia retinopathy
ICC Cytoplas PC and Ov ca Nuclei neurones tumors Nuclei of CNS neurones,breast and lung ca Retinal neurones, rods, cones
55
Benign cystic lesions in the brain that may
cause sudden death colloid cyst of the third
ventricle Other cystic lesions
56
A209/01
57

• CONCLUSION
• 1. Brain tumours classified into intrinsic,
• extrinsic and spread from adjacent structures
• Adults usually present with supratentorial
  tumours
• Commonest primary tumour in adults gliomas. gt65
• metastatic tumours common
• Paraneoplastic syndromes non-metastatic
  complications of an underlying malignancy.