1. CNS tumors
Dr. Waleed Dabbas

2. Background

3. Frequency
Children : -Posterior fossa tumors ( Infra-Tentorial). -Astrocytoma, Ependymoma, and Medulloblastoma. Adults : -The most common malignant brain tumor in adults is GBM.

4. Incidence
Overall incidence of primary brain tumor is 9.5 cases per 100,000 population in the United States.
More than 50% are gliomas
Brain tumors represent 30% of all childhood malignancies

5. Epidemiology Gender Slight increased brain tumors in males Two peaks
Smaller peak in pediatric age group
Second peak in elderly population between years of age

6. Etiology and Risk Factors
Several genetic disorders cause or increase risk for brain tumors.
Neurofibromatosis
Tuberous sclerosis
Turcots syndrome
Osler-Weber-Rendu syndrome
Li-Fraumeni syndrome

7. Symptoms and signs Seizures – 54% at presentation Headaches – 71%
Mental change – 53%
Hemiparesis – 43%
Cranial nerve – 14%

8. Brain tumor syndromes Seizure : Cortical lesion
Behavioral : Anterior Cranial fossa.
Weakness: internal capsule or primary motor cortex
Vision : optic nerve compression
Speech: Broca’s area.
Endocrine : prolactinoma , etc..
Torticollis : post. Cranial fossa tumor compressing the XI nerve.
Anosmia : Foster-Kennedy Syndrome ( ant. Cranial fossa tumor ) “ ipsilateral Optic nerve atrophy + Contralateral papilledema “

9. Diagnosis Imaging studies available are MRI CT scan
On MRI the high grade of malignant gliomas appear as contrast enhancing mass lesions
CT scan
Contrast enhanced CT scan for use if MRI is unavailable
Nuclear medicine studies
Brain scan not used much now

10. Classifications
By origin : Primary VS secondary By location : supratentorial VS infratentorial By cell type e.g. glioma,menengioma,oligodendroglioma>>> By grade: 1,2,3,4 Benign VS malignant ?

11. Meningioma
Benign
Can grow at any part of the meninges, common sites: cerebral convexity, falx cerebri, parasagital, Optic nerve, CP angle, INTRAVENTRICULAR !!!
Age:
More in Female “ progesterone receptors on meningiothelial cells” , ALAD2 gene “ inc. lead” , Long arm Ch.22.
Malignant : Atypical meningioma, MeningioSarcoma.
Intraventricular meningioma : 80% of these in the lateral ventricles. Despite this, intraventricular meningioma is the most common trigonal mass in the adult. They are thought to form via the infolding of meningeal tissue during the formation of the choroid plexus

12. Menengiomas Benign, Rarely malignanat
Can grow at any part of the meninges, common sites: cerebral convexity, falx cerebri, parasagital.
Age:
More in Female “ progesterone receptors on meningiothelial cells” .

13. Hemangioblastoma Benign
Most common adult Primary Post. Cranial Fossa tumor
Highly Vascularized
Two forms : Cystic VS. Solid.

14. Neuroepithelial Tumors GLIOMA
Type of Cells: A. Astrocytic tumors B. Oligodendroglial tumors C. Ependymal tumors D. Mixed gliomas E. Choroid plexus tumors Grade: Low VS. High Location: SupraTentorial VS. InfraTent.

15. Astrocytoma
Grade I & II:- Superficial & Infratentorial. ( Benign ) - Young ages(Juv. Cerebellar Astrocytoma) Grade III & IV: Anaplastic Astrocytoma Glioblastoma Multiforme

16. Oligodendroglioma Microcalcification is common.
Well differentiated VS Anaplastic “less common”
MicroCalcification.

17. Ependymoma less than 2% of brain tumors.
Ependymal cells that line the ventricles.
less than 2% of brain tumors.
Usually low grade histology but have a high grade of recurrence
Supratentorial  3rd ventricle+malignant
Infratentorial  4th ventricle+Benign“more common”

18. Choroid Plexus Papilloma * Rare *
From the Choroid plexus  inc.CSF production
Hydrocephalus.
Supratentorial  Children ( Lateral Vent. )
Infratentorial  Adult ( Rare )

19. Medulloblastoma PNET (30% of pediatric brain tumors )
Midline in the vermis of the cerebellum & extend to the 4th ventricle.
Young, hydroceph., ataxia.
Spread through CNS, bone.

20. Pituitary tumors
Pituitary tumors have three features: Local mass effect Visual field disturbance (bitemporal hemianopia). headache Hormone deficiency: deficiency tend to first suppress LH and GH, followed in sequence by loss of TSH,ACTH and FSH Hormone excess

21. Craniopharyngioma
Derived from remnants of the structures that give rise to pituitary gland. Mass effect (headache, visual field defect) Hormonal deficiencies Could be cystic or solid with or without calcification.

22. Spinal tumors
1 Extradural : Secondary deposits in the spine(commonest) primary vertebral bony tumors(osteoclastoma,myeloma) Lymphomas 2 Intradural extramedullary Meningioma Neurofibroma 3 Intramedullary (rare) Glioma Ependymoma Others such as hemangioma

24. Involvement of the CNS by Systemic Cancer
Brain metastases occur in 25-35% of all cancers.
The peak incidence of brain metastases is bimodal ages 0-10 years and age years.
Location
50% of brain metastases are supratentorial
Lung cancer and breast cancers are most common metastatic tumors to the head.
Melanoma has greatest potential for metastasis to the brain.
Approximately 40% of all patients with systemic disease develop brain metastases.

25. Prognostic Factors
Include pathological grade, patient age and overall patient function at the time of diagnosis and duration of symptoms.
Immediate survival with resection, radiotherapy and chemotherapy is three years for those with anaplastic astrocytoma and one year for those with glioblastoma multiform.

26. Treatment Includes supportive and definitive treatment
Supportive agents are anticonvulsant and corticosteroids
Definitive therapy for intracranial tumor is surgery

27. Treatment Surgical tools available include: Stereotactic frames
Definition provided three dimensional imaging system for accurate targeting of brain lesions identifed on CT or MRI scan
Image based guiding system
Definition frameless for image guided stereotactic system. Use computer technology to co-register pre-operative imaging studies with intra-operative head position. These systems facilitate more complete tumor resection.

28. Radiation Therapy
Radiation plays a central role in treatment of brain tumors in adults.
Whole brain versus partial brain radiation
Dose to the response of low grade gliomas
Other alternatives to conventional radiotherapy include hyperfractionated radiotherapy or use of radiosensitizers and boron neutron capture therapy

29. Chemotherapy Chemotherapy regimens for gliomas include:
Single agent BCN4 or combination chemotherapy of CCNU, procarbazine and vincristine