Presenter: Dr. Sabir AhmedChairperson: Dr. S.D. Kshirsagar

A wide variety of tumors affect the brain and spine.

Primary benign and malignant tumors arise from the various elements of the CNS, including neurons, glia, and meninges. Tumors metastasize to the CNS from many primary sources.

Presentation varies widely depending on relevant neuroanatomy. Prognosis depends on histology and anatomy

Modern brain tumor centers use team approaches to CNS tumors, as patients may require a combination of surgery, radiation therapy, chemotherapy and research protocol enrollment.

Nervous system may be divided into Central nervous system - brain - spinal cord peripheral nervous system - peripheral nerves - ganglia The brain consists of (i) the cerebrum comprising 2 large cerebral hemisphere (ii) the cerebellum (iii) brainstem - midbrain - pons - medulla

The cerebrum made up of 2 cerebral hemispheres, partially separeted from each other by the median longitudinal fissure.

The 2 hemispheres are connected to each other by corpus callosum

Each ventricle contains a cavity, called the lateral ventricle.

Each cerebral hemisphere is divided into 4 lobes-1. Frontal 3 2. Parietal3. Occipital4. TemporalThe sulci separating the lobes on this surface

are

1. Central sulcus: separating frontal and parietal lobe

2. Lateral sucus: separating temporal lobe from frontal and parietal lobe

3. parieto-occipital sulcus: is a sulcus of medial surface, separating occipital from parital lobe

4. Preoccipital notch: is an indentation on the inferolateral border.

2 1 3 4

Duramatter Arachnoid matter Pia matter

The specialized cells that constitute the nervous syatem are called –nurone.

Nurones are supported by special kind of connective tissue called- neuroglia

Neuron consist of - cell body which gives off variable number of

processes. - most neurons give off a number of short

branching called dendrites and one longer process called axon.

In case of peripheral nerves Most axons surrounded by myelin sheath, formed by - Schwann cells In CNS axons surrounded by neuroglial cells - oligidendrocytes

Functional differences between axon & dendrites axon dendrites

In an axon nerve impulse travels away from cell body

Nerve impulse travels towards the cell body

Astrocytes Microglia OligodendrocytesAstrocytes : These are star shaped cells present in all part

of the brain Types 1. fibrous astrocytes- (present in white matter) 2. protoplasmic astrocytes- (present in gray

matter)Microglia: These are the phagocytic cells which enters

the tissues of nervous system from blood.Oligodendrocytes:These are the cells forming myelin sheath

around the nerve fibers in central nervous system

Although either benign or malignant, almost all brain tumours are malignant in the sense that they may lead eventually to death if not treated.

In general, the incidence of primary brain tumors is higher in whites than in blacks, and mortality is higher in males than in females.

Brain tumours are responsible for 2 per cent of all cancer deaths.

The incidence varies with age. In children tumours of the CNS comprise 20 per cent of all childhood malignancies. There is a peak at 2 years followed by a decline for the rest of the first decade. The incidence then slowly increases, peaking at 20 per 100 000 in late adulthood.

Intracranial tumour can be classified in different ways: primary versus secondary, paediatric versus adult, by cell of origin, or by location in the nervous system.

Classification of brain tumour (according to cell of origin)

Neuroepithelial metastatic meningioma pituitary

Tomour tumour tumour tumour

50% 15% 15% 8%

Neuro epithelial tumours gliomas - astrocytomas - oligodendroglioma - ependymoma - choroid plexus tumour pineal tumours nuronal tumours - ganglioglioma - gangliocytoma - neuroblastoma medulloblastomaNerve sheath tumours - acoustic neuromaMeningeal tumours - meningiomaPituitary tumours - germ cell tumour - germinoma - teratoma Lymphoma Tumour like malformations - craniopharyngioma - epidermoid tumour - dermoid tumour - colloid cystMetastatic tumours Contageous extention from regional tumour: - glomus tumour

1. Chromosomal anomalies: von Recklinghausen’s disease

2. Immunosuppression: primary CNS lymphoma3. Addition of oncogenes in genome and loss of

normally occurring tumour suppresser genes.

4. Mutation in p53 tumour suppresser gene: astrocytoma and meningioma

5. Cranial irradiation: for tenia capitis leads to astrocytoma and meningioma

supratentorial

adults % Children(<15yrs

%

Anaplastic astrocytoma

347 40 5 7

meningioma 134 15 - -

Metastasis 105 12 - -

astrocytoma 73 8 5 7

Pituitary adenoma

31 4 - -

craneopharyngioma

13 1 9 13

oligodendroglioma

9 1 1 1

Colloid cyst 4 <1 - -

lymphoma 2 <1 - -

others 11 1 6 9

Infratentorial

adults % Children %

neuroma 50 6 -

metastasis 39 4 -

haemangioblastoma

17 2 -

astrocytoma 12 1 19 27

meningioma 12 1 -

medulloblastoma

6 <1 17 24

Dermoid/ epidermoid

3 <1 1 1

ependymoma

4 6

others 8 1 3 3

Symptoms tend to develop insidiously, gradually progressing over few weeks or years.

Occasionally tumour present acutely due to haemorrhage or the development of hydrocephalus.

supratentorial infratentorial tumour tumour sings and symptoms Mass of ICP and brain shift CSF Effects

outflow tentorial tonsillar

obstruction herniation herniation

Focal epilepsy Damage damage function Cr N. damage I-VI cerebral cerebellar Cr N. damage

III- XII

Raised intracraneal pressure- headache(morning & progressive), papilloedema(disturbance of vision)

Brain shift – vomiting, deteration of conscious level, pupillary dilatation

Epilepsy – generalised, partial(simple or complex), partial progressing to genarelised.

Partial motor seizures partial sensory seizures

origin- motor cortex origin – sensory cortex

- Tonic/clonic seizures numbness tingling in

- In contralateral face and limb- Face and limbs- pure

visual/auditory- seizures are rare

- complex partial seizures: arise from the - medial temporal lobe- formed visual or auditory- hallucinations, awareness of abnormal taste,- feeling of fear, déjà vu, unfamiliarity and - depersonalisation and automatisms.

Disturbed function: Supratentorial Higher cortical dysfunction before knowing higher cortical dysfunction we should know normal

function of cortex.Right and left hemisphere function:- left hemisphere is dominant in right handed person left hemisphere is dominant in left handed person(in 75% of cases).

language R L language dependent memory

Visual and spatial perceptionVisual(non language dependent memory)

Frontal lobe function Impairment of frontal lobe function

Precentral gyrus: motor cortex, contralateral movement- face arm trunk leg.

Prefrontal gyrus:- monoplegia/ hemiplegia depending on the extent of damage

Broca’s area: dominent hemisphere expressive centre for speech.

Broca’s are:- broca’s dysphasia

Supplimentary moter area: contralateral head and eye turning.

Supplimentary motor area: paralysis of head and eye movement to opposite side.Head & eye turn towards diseased hemisphere

Prefrontal area:- personality, initiative

Prefrontal area:- change of personality with antisocial behaviour/loss of inhibition. Disturbance of gait- gait apraxia. 3 prefrontal syndrome- orbitofrontal syndrome, frontal convexity syndrome, medial frontal syndrome.

Paracentral lobule:- cortical inhibition of bladder and bowel voiding

Paracentral lobule:- incontinence of urine and faeces.Loss of cortical inhibition

Parietal lobe function Impairment of parietal lobe function

Sensory cortex: (represents similar to motor cortex)---receives afferent pathways for - appreciation of posture - touch - passive movement

Contraleteral disturbances of cortical sensation - postural sensation disturbed - sensation of passive movement disturbed - accurate localization of light touch disturbed - 2 point discrimination disturbed - asterognosis

Supramarginal angular gyrus: (dominant hemisphere) - Wernicke’s language area - receptive area where auditory , visual aspect of comprehension are integrated.

Supramarginal angular gyrus: (dominant hemisphere)Gerstmann’s syn-confusion of right & left limb.-Finger agnosia -Acalculia-Agraphia

Supramarginal angular gyrus: (non dominant hemisphere) - concept of body image - awareness of external movement - skills of handling numbers/calculation - visual pathway (optic radiation pass through parietal lobe)

Supramarginal angular gyrus: (non dominant hemisphere)-Unaware of opposite limbs-Anosognosia-Geographical agnosia-Constitutional apraxia: - cannot copy geometric pattern-Damage of optic radiation: lower homonymous quadranopia

Temporal lobe function Impairment of function

Auditory cortex: dominant lobe: hearing of language no dominant lobe: hearing of sound, rhythm, music.

Auditory cortex: dominant lobe: cortical deafness nondominant lobe: amusia

Middle and inferior temporal gyri: - learning - memory

Middle and inferior temporal gyri: - disturbance of –memory - learning - complex partial seizures - post ictal amnesia

Limbic lobe: - sensation of olfaction - emotional/effective behaviour

Limbic lobe: - olfactory hallucination with complex partial seizures - aggressive emotional behaviour - inability to establish new memories.

Visual pathway: - deep in temporal lobe

Visual pathway: upper homonymous quadranopiap

Occipital lobe function Impirement ofOccipital lobe function

Visual cortex : striate cortex Visual cortex : homonymous hemianopia with sparing of macula

Cortical blindness with preservation of light reflex.

Visual cortex : parastriate cortex Visual cortex : parastriate cortexBalint syndrome: (BL parieto occipital lesion) inability to direct voluntary gage, associated with visual agnosiaVisual illusion: micropsia- object appear smaller macropsia- object appear largerProsapagnosia: ( occipito-temporal jn.) patient can see but cannot name familial face.Anton syndrome: involvement of both striate cortex & parastriate cortex impairment of vision patient unaware of visual loss

Chest Xray ESR for metastatic workup

Skull Xray: 1. Calcification - oligodendroglioma - meningioma - craniopharyngioma

Skull Xray: 2. sings of raised

intracranial pressure: -suture

separation(diastasis) - “beaten brass”

appreance

Skull Xray: 3. osteolytic lesion;

primary/secondary bone tumour. - dermiod/epidermoid - chordoma - nasopharyngeal carcinoma - myeloma - reticulosis

Skull Xray:4. erosion of posterior

clinoids - due to local pressure -

craniopharyngioma5. Pineal shift in Towne’s

view

CT scanning1. Effect on adjacent bone - meningioma - hyperostosis

CT scanning single or multiple lesions - if multiple metastasis

CT scanning effect of contrast enhancement none- low grade astrocytoma

irregular- malignant astrocytoma

homogenous- meningioma

CT scanning mass effect:

- midline shift - ventricular compression

- hydrocephalus (secondary to 3rd ventricular

of posterior fossa lesion

High definition scan: indication - pituitary - orbital - posterior fossa tumour - tumour of skull baseCoronal and sagital

reconstruction - useful in diagnosing

vertical extent of the tumour - and its relationship with

other structure

MRI indication - tumours around the skull base - craneocervical junction - brainstemAdvantage of MRI -coronal and sagital section gives - exact anatomical relationship to the

sulci and gyri, ventricles, the falx and tentorium cerebelli.

- paramagnetic enhancement - IV gadolinium increases sensitivity

of detection and clarifies the site of origin. - delineate the border between

tumour and surrounding edema - MRI appears more sensitive than CT

scanning in identifying - small tumours - multiple lesions-

metastasis

Angiography/ MRA: reveal - tumour ‘blush’ - vessel displacement - preoperative

information - for identifying

feeding to vascular tumours - tumour

involvement and constriction of major vessels.

CSF examination: lumber puncture is contraindicated

in cerebral tumours. if CSF is obtained by another sources - ventricular drainage - or shunt insertion then cytological examination may

reveal tumour cells

Tumour markers: Glial Fibrillary Acidic Protein(GFAP) - for glial tumours Cytokeratin Epithelial Membrane Antigen(EMA) for metastatic

carcinoma

Epidermal Growth Factor- differentiate between - high grade & low

grade tumour

-

Steroid therapy: - to reduce edema surrounding the intracranial

tumour. - sellar/paraseller tumour occasionally present

with steroid insufficiency. In these cases steroid cover is an essential prerequisite

of any anesthetic and operative procedure. Dose: - A loading dose of 12mg IV dexamethasone - followed by 4mg qid. - after several days of treatment, gradual dose

reduction minimizes the risk of unwanted side effects.

Operative management: Approaches Craniotomy:- flap of bone is cut

and reflected. - If necessary, combined with either a

stereotactic frame - or preferably an image guided

system(frameless, steriotaxy) to give accurate lesion localisation

Burr hole surgery: For stereotactic or handheld, USG

guided biopsy

Transphenoidal route: indication- pituitary surgery through the sphenoid sinus to the

pituitary

Transoral route: Indication: - brain stem surgery - upper cervical cord surgery - neurofibroma - chordoma Method: removal of arch of atlas, odontoid

peg and clivus provide access to anterior aspect

of brain

Operative procedure: The subsequent procedure

biopsy partial tumour removal internal decompression complete removal

Depends on the nature of the tumour & site.

Primary malignant tumour : complete removal of tumour is not possible due to its infiltrative nature. So operation is restricted to - biopsy

- tumour decompression

Complete removal is done for - meningioma - craniopharyngioma

Radiotherapy : - Megavoltage xray - gamma rays from cobalt60. - electron beam from linear

accelerator. - accelerated particles from a

cyclotron (e.g. neutrons,

nuclei of helium, protons)

Effect of radiotherapy – depends on total dose(usually upto 60Gy) and duration of therapy.

Radiotherapy : Aim : to provide highest possible dose to the specific

region, while minimal irradiation to adjacent normal brain.

Indication: In malignant tumour: - malignant astrocytoma - metastasis - medulloblastoma - germinomaIn benign tumours - pituitary adenoma - craniopharyngioma

Radiotherapy : Method : 1. Stereotactic

irradiation: Multiple covering

beams from a linear accelerator or from multiple cobalt sources

focused on a selected target

Radiotherapy : 2. Interstitial techniques:Tumour is treated from within(brachytherapy) - by implantation of multiple radioactive

seeds. e.g. iodine125.3. Conformal therapy: - standard radiotherapy is administered - beam are shaped by use of variable

collimeters/blocks.

Radiotherapy : 4. Whole neural axis irrediation: indication: - for tumour spread through CSF - medulloblastoma.Complication of radiotherapy:

Increased edema

During treatment

Reversible

demylination After weeks or months

Usually reversible

radionecrosis In usually 1-2 yrs(range from 6m-10yrs)

irreversible

Drugs commonly used: - nitrosoureas

- Procarbazine - Vincristine - methotrexate

Malignant astrocytoma: -nitrosoureas are most effective drug - commonly used treatment for relapse

patient Low grade tumour or benign tumour: - chemotherapy has limited value Medulloblastoma: - respond to treatment but value of

treatment of patient survival – is unclear. Primary germ cell tumour & primary

cerebral lymphoma: - chemotherapy has a role.

New approaches: Cell targeting: monoclonal antibody is used to carry - cytotoxic drug - toxins - radionuleotide to the tumour cells Improving access: modifying BBB with mannitol or

preliminary binding with liposomes may improve the passage of cytotoxic drug and monoclonal antibodies to tumour tissue.

Intracarotid injection: of slow releasing biodegredable polymers of nitrosoureas in patient with

- malignant glioma Invitro chemosentitivity testing: utilizes cultured

tumour cells from biopsy meterial.