2 INCIDENCE 2 nd most common malignancy in

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INCIDENCE • 2 nd most common malignancy in children after leukemia. • 20% of all childhood malignancy 3

Etiology &Predisposing factors 1 -Unkown 2 - Environmental factors( diet, smoking, alcohol Radiation). 3 - Immunosuppression ( transplant. , AIDS) 4 - Mutation or deletion of specific genes 5 - Irradiation 4

Classification (site) Infratentorial Supratentorial • Tentorium: A fold of the dura mater which cover and separates the cerebellum from the occipital lobes of cerebrum 5

Classification Infratentorial (60%) 1 - posterior fossa (medulloblastoma, meningioma, ependymoma) 2 - Brain stem (low grade glioma) Supratentorial (40%) 1 - cerebral hemisphere (low , high grade glioma, ependymoma, meningioma) 2 - sella (crainiohparyngioma, pitutary adenoma, optic nerve glioma 3 - pineal body (pineoblastoma) 6

Clinical manifestations Depend on size, location and growth rate: 1 - slowly growing t ----- massive shift of the normal structure as it reach large seize. 1 - rapidly growing t ----- early symptoms and signs with small size. 3 - manifestations of increased ICT 7

General manifestations(symptoms ) • • Headache Vomiting Visual defect Mental disturbance (change of personality) Endocrine disturbance Cranial enlargement and irritability in infancy Gait disturbance Seizure( focal). 8

Localizing signs False Localizing signs (compression on brain tissue by ICT) - compression on: 6 th nerve ------- diplobia compression on: vagus n : bradycardia and irregular pulse compression on : vasomoter center : systemic hypertension compression on : medullary respiratory centre : irregular respiration Herniation of cerebllar vermis: ataxia and nystagmus head tilting Pressure on brainstem reticular formation: coma 9

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1 - Cerebellar astrocytoma Most common posterior fossa Cystic t arise near midline but extend to one cerebellar hemisphere True Localizing signs: (a)Signs of unilateral cerebellar dysfunction on the side of the lesion: ataxia , gait disturbance , nystagmus 11

(b) Cerebellar fits : seizure like states due to pressure on vital structure in the brainstem loss of consciousness , neck retraction, dilatation of the pupils and respiratory irregularity. (c) Hydrocephalus and s, s of increased ICT: obstruction of aqueduct of sylvius or fourth ventricle. 12

Treatment 1 - surgery • 2 - chemotherapy • 3 - radiotherapy • 13

CT SCAN 14

MRI 15

2 - Cerebellar medulloblastoma • 2 nd most common pft(posterior fossa tumor) • Common below 7 years • Solid midline t arise from the cerebellar vermis. and invade both cerebellar hemisphere, cerebral cortex and spinal cord • 20% of primary central nervous system t in children 16

True Localizing signs: • ataxia , hydrocephalus and signs of increased ICT other symptoms: Hydrocephalus 17

Treatment Surgical removal Residual tumor average Radiotherapy only high Radio+ chem. 18

Medulloblastoma. Unenhanced CT shows a high-density midline tumor in the posterior fossa with a small amount of surrounding vasogenic edema exerting mass effect on the fourth ventricle, with a moderate degree of hydrocephalus. 19

Medulloblastoma. Axial T 1 weighted postcontrast image demonstrates an irregular, heterogenous enhancing mass. Note the dilatation of both temporal horns, indicating obstructive hydrocephalus 20

3 - Brain stem gliomas • 3 rd most common pft , no evidence of increased ICT True Localizing signs: a) Multiple bilateral cranial nerve palsies: diplopia(6 th nerve), facial weakness(7 th n), dysphagia, dysphonia(9, 10) b) Bilateral pyramidal tract signs (hypertonia, hyperreflexia, positive babinski sign). c) Gait disturbance (ataxia). 21

Treatment (palliative) Surgery: not usually possible (near to vital structure, limited room for expansion) Radiotherapy : limited field radiation Chemotherapy : not improve survival 22

CT scan of a case with brainstem glioma 23

4 - Ependymomas • Arise from the floor of the 4 th ventricle • Early obstruction to CSF flow early signs of increased ICT • Calcification 24

Grades 3, 4 Treatment Surgery (debalking) radiotherapy chemotherapy 25

• Brain ependymoma. Ependymoma arising from the fourth ventricle. A 13 year-old girl with recent onset of headache, nausea, vomiting, and papilledema. Nonenhanced axial CT image demonstrates a large, round tumor arising from the fourth ventricle with attenuating nodular calcifications. Obstructive hydrocephalus is noted with frontal lobe white matter of low attenuation resulting from subependymal cerebrospinal fluid absorption. 26

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1 -Craniopharyngioma • the most Supratentorial t • Slowly growing (benign histology but malignant behavior) • Consist of cystic and solid areas with calcification • arising from remnants of the craniopharyngeal duct • May be confined to sella turcica or extend to compress optic nerve system 28

C/P • Progressive visual loss • Increased ICT • Endocrine disorders : short stature and growth failure. X ray skull: calcification of intra or supra sellar location and increased ICT 29

Sagittal non enhanced T 1 weighted image demonstrates a heterogeneous, cystic mass (arrows) in the suprasellar space. 30

Treatment surgery Total resection subtotal radiotherapy No role to chem. but recently interferon α 2 a 31

2 - CHOROID PLEXUS PAPILLOMA • Most common prior to 3 yr of age. • It usually arises from choroid plexus of a lateral ventricle (less commonly 3 rd and 4 th ventricles )-- increased CSF production --- hydrocephalus. • Ct scan detect the tumor mass and hydrocephalus. • Malignant choroid plexus carcinoma is extremely vascular and invasive. • Treatment : mainly surgical resection. 32

MRI. demonstrates the strongly enhancing lateral ventricular mass 33

3 - LEUKEMIA • It may invade : A. Leptomeninges ----- increased intracranial pressure B. Brain parenchyma (Focal signs). c. CNS Hge 34

4 - Cerebral cortex tumors Cerebral ASTROCYTOMA • They are located in the cerebral hemisphere The true localizing signs (according to the site of the tumor ) are : A. Frontal lobe tumor * irritative ( early) lesion : • chronic focal convulsion of opposite side. Destructive lesion : • personality changes: lethargic, irritable, forgetful Progressive motor weakness of UMNL type in the 35 opposite side of the body

b. Parietal lobe tumor * Irritative lesion : fits of opposite side of body. • destructive lesion: loss of cortical sensation. • C. Occipital lobe tumor • Irritative lesion : visual hallucination ( flashes of light). destructive lesion : visual affection. D. Temporal lobe tumor * Irritative lesion : epilepsy. *destructive lesion: loss of hearing, 36

5 - PITUTARY T • Pituitary adenomas are divided into 2 categories by their size : v. Microadenomas: < 1 cm are rarely damage the rest of the pituitary or neighboring tissues. They produce symptoms because of the excessive amounts of hormone they secrete. • Macroadenomas: >1 cm. have they cause symptoms of damage of the normal pituitary tissue or nearby nerves especially the optic nerve and manifestation of hormonal secretion 37

Manifestation of pitutary t A. hormonal manifestations • gigantism or acromegaly. • cushing syndrome. • hypopituitarism. B. Neurological manifestations (compression of adjacent structures ) 38

treatment Surgical removal Radiation therapy using high-doses of x-rays to kill tumor cells 39

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1 - plain X-ray signs of increased intracranial pressure: In infancy : seperation of suture and erosion of posterior clenoids IN childhood : increased convolutional markings( silver beaten ) some tumors may show calcification (craniophyaryngioma, some ependymoma) 41

ICT 42

2 - CT SCAN • Detect 95% of brain tumors even without contrast. • Not useful in posterior fossa t ---MRI. • Useful than MRI in (calcified t and unstable patients) 3 - MRI 43

4 -Biopsy • The only test that can absolutely make a diagnosis of a brain tumor is a biopsy. • A needle biopsy: Tissue is removed using the needle, which is frequently guided by CT scanning. 44

Spread of brain tumor • Local: confined to: one hemisphere in one part of brain (infra/supratentorial); meninges; invading/encroaching on ventricular system • Regional crossing midline or tentorium invades bone, blood vessel, nerves, spinal cord • Distant circulating cells in CSF; extension to nasal cavity, nasopharynx, posterior pharynx; outside CNS 45

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