1. GLIOMAS Are tumors of the CNS that arise from glial cells
They constitute 45% to 55%
of intracranial tumors
They are the most common tumors of the CNS

2. WHO CLASSIFICATION OF NEUROEPITHELIAL TUMORS
WHO CLASSIFICATION OF NEUROEPITHELIAL TUMORS
( World Health Organization)
1. Astrocytic tumors
         Pilocytic astrocytoma
-         Astrocytoma (fibrous gemistocytic)
-          Anaplastic astrocytoma
2. Oligodendroglial tumors
  Oligodendroglioma
-         Mixed oligoastrocytoma
-         Anaplastic oligodendroglioma
3. Tumors from ependymal cells and choroid
plexus
-         Ependymoma
-         Anaplastic ependymoma
-         Choroid plexus papilloma
-         Anaplastic choroid plexus papilloma

3. 4. Poorly differentiated tumors and embryonic stem cells Glioblastoma
4. Poorly differentiated tumors and embryonic stem cells
Glioblastoma
Medulloblastoma
5. Tumors of pineal cell origin
Pinealoma
Pinealoblastoma
6. Neuronal tumors
Gangliogloioma
Gangliocytoma
Neuroblastoma 

4. KERNOHAN GRADING SYSTEM OF ASTROCYNOMAS
Grade 1
Increased number of cells
Essentially of normal cytology form
Pilocytic astrocytoma falls into this category
Grade 2
Increased number of cells, but most of the cells are astrocytes
Hyperchromatic nuclei
No mitoses or necroses
Few fine vessels

5. Grade 3 Many cells appear as astrocytes Pleomorphism Few mitotic figures Necrosis frequently Partial endothelial proliferation in vessels Grade 4 Few normal astrocytes appear Pleomorphism prevails Many bizarre mitoses Necroses frequently Endothelial proliferation in vessels prevails

6. 1) PILOCYTIC ASTROCYTOMA
ASTROCYTIC TUMORS
1) PILOCYTIC ASTROCYTOMA
Average age: 13 years
Percentage: 2% of gliomas
Localization:
- Cerebellum / strain (61%)
- Optic chiasm / hypothalamus (28%)
- Cerebral hemispheres (11%)

7. Clinical profile - Chiasmal tumors : visual deficits,
endocrinological dysfunctions,
symptoms of hydrocephalus
- Cerebral hemispheres tumors : headache,
epileptic attacks, motor deficit

8. Paraclinical examinations
These tumors are usually cystic and have a
node from solid tissue
- Head Computed Tomography :
Slightly hypodense or isodense.
Calcification occurs at 22%.
Uptake of the injected contrast
by solid tissue of the tumor.
- Magnetic resonance imaging (MRI) of the brain : By injecting 
gadolinium, uptake by the solid tissue and the
wall of the tumor

10. Treatment - Surgical resection if possible
- Total resection is rarely possible
Radiotherapy is controversial.
Some doctors recommend it after subtotal resection of tumor
and if the patient
is older than 3

11. Result 81% survive for 10 years after subtotal resection of tumor and
radiotherapy
54% survive for 20 years

12. HISTOLOGICAL PROFILE Fusiform cells with wavy fibrous processes
- Rosenthal fibers are common but not
essential
- Eosinophilic granular particles are common
Microcystic areas of small stellate
astrocytes alternate with pilocytic
areas
There are macrophages, predominantly in tumors
located in the cerebral hemispheres

14. 2) LOW GRADE ASTROCYTOMA
Average age: 35 to 45 years
Percentage: 5% to 25% of gliomas
Localization:
- In cerebral hemispheres, especially in the frontal lobe
(40%), in the temporal lobe (25%) and parietal
lobe (25%)
- Other localization such as in thalamus, mesencephalon, pons (10%)

15. Clinical profile - Epileptic attacks are the most frequent (65%)
- Symptoms of increased intracranial pressure
(40%), personality disorders (15%), or
focal neurological deficits which are
less frequent (10%)

16. Paraclinical examinations
- Head Computed Tomography :
Hypodense or sometimes isodense.
No significant oedima appears.
Rarely, uptake of the contrast
- Magnetic resonance imaging (MRI) of the brain :
The lesion is usually clearly defined.
Increased T2 signal. The signal is
homogeneous.
Small oedema.
By injecting gadolinium the image is the same as
in the CT.

18. Treatment Surgical removal Postoperative radiotherapy is
controversial.
- Chemotherapy is contraindicated

19. Result Average survival is around 3.5 years
5-year survival is around 26% to 33%
Radiotherapy prolongs life by 1 to 3 years
but not more.

20. 86% of astrocytomas that relapse are already anaplastic Prognostic factors are age, physical condition of the patient and the extent of surgical resection

21. HISTOLOGICAL PROFILE Moderate polycytosis The nuclei may appear
large but without any significant
pleomorphism
No vascular reproduction
No necrosis

23. 3) ANAPLASTIC ASTROCYTOMA
Average age: 46 years
Percentage: 10% to 30% of gliomas
Localization:
- Cerebral hemispheres, especially the frontal, temporal and parietal lobe. The rates are the same as in
low-grade astrocytomas
- Thalamus, mesencephalon, pons are less likely

24. Clinical profile - Epileptic attacks are the initial
symptoms of at least 50% of patients
- Symptoms of increased intracranial
pressure (40%), personality disorders
(15% to 20%), or focal neurological
deficits (10% to 15%)
- Average duration of symptoms is 16
months

25. Paraclinical examinations
- Head Computed Tomography :
hypodense
significant oedima.
Often the tumor boundaries are not defined
Contrast uptake at 80% to 90 of cases
- Magnetic resonance imaging (MRI) of the brain :
Less clearly defined tumor boundaries
of the low-grade astrocytomas
Moderate oedema.
More inhomogeneous signal than in low-grade
astrocytomas
Contrast uptake varies
Minimum hemosiderin

27. Treatment Surgical removal Postoperative radiotherapy
depends on the extent of tumor resection
In case of recurrence
reoperation, chemotherapy,
brachytherapy and radiotherapy are recommended

28. Result 2-year survival is around 40% to 50%
after surgery and radiotherapy
and chemotherapy

29. Prognostic factors are
age, functional status
of the patient and the
residual tumor
45% of tumors
that relapse are already
higher grade glioma

30. HISTOLOGICAL PROFILE Moderate polycytosis
Moderate pleomorphism of cells and
of nuclei
Local anaplastic changes
Necrosis points

32. 4) GLIOBLASTOMA MULTIFORME (GBM)
Average age: years
Percentage: 45% to 50% of gliomas
Localization:
- Cerebral hemispheres mainly (40% in the frontal
lobe, 25% in the temporal lobe and 25% in the parietal lobe)
- Sometimes in the corpus callosum (butterfly glioma)
- In the strain less often

33. Clinical profile - Epileptic attacks constitute 32%
- Symptoms of increased intracranial pressure
(86% headache, 45% nausea and vomiting
Personality Disorders (47%) and motor
deficits (44%), also often symptoms

34. Paraclinical examinations
- Head Computed Tomography :
Heterogeneous hyperintense area highlights necrotic
areas
Significant oedima and displacement of midline structures
Blurred boundaries
At least 95% of these tumors take up contrast
There are instances that the tumor crosses the midline
- Magnetic resonance imaging (MRI) of the brain :
The tumor boundaries cannot be determined
Large oedema and displacement of midline structures
Inhomogeneous signal inside the tumor
Contrast uptake is the same as that visualized in CT
Bleeding is often and so is the presence of haemosiderin

36. Treatment Surgical removal Postoperative radiotherapy depends on
the extent of tumor resection
In case of recurrence
reoperation, chemotherapy, brachytherapy and radiotherapy are recommended

37. Result - 2-year survival is around 10%
The average survival after surgery,
surgery and radiation therapy, or surgery
and radiotherapy and chemotherapy is 4,
9.25, and 10 months respectively
Reoperation and / or brachytherapy may
increase survival by 9 to 12 months
in some patients

38. Prognostic factors are age, functional status of the patient and the residual tumor after surgery and radiotherapy Some neurosurgeons recommend only biopsy and adjuvant therapy for high malignancy supratentorial tumors

39. Pleomorphism of cells and of cytoplasm Often vascular hyperplasias
HISTOLOGICAL PROFILE
Polycytosis
Pleomorphism of cells and
of cytoplasm
Often vascular hyperplasias
Necroses frequently

41. 6) OLIGODENDROGLIOMA Average age: 43 years
Percentage: 4% to 6% of gliomas
Localization:
- Cerebral hemispheres (50%) in the frontal
lobe, (15% to 25%) in the temporal lobe and in the
parietal lobe
- Occipital (5%) rarely

42. Clinical profile - Epileptic attacks constitute > 50%
- Headache at 30% to 78%
- personality disorders, visual
disturbances, and focal deficits
(in the absence of seizures)

43. Paraclinical examinations
- Head Computed Tomography :
-Hypodense or isodense.
- Areas with calcification seen in more than 70% of cases
- Cystic areas and bleeding are rare
- When there are anaplastic tumor elements calcification occurs less often
- Oedema and contrast uptake are common only in anaplastic tumors
- Magnetic resonance imaging (MRI) of the brain :
- Moderate or slight contrast uptake
- Heterogeneous low frequency signal, due to calcination

45. Treatment Surgical removal Radiotherapy after total resection
Some surgeons are not in favor of total resection of space lesion
They recommend chemotherapy and / or re-operation on residual tumor

46. Result - Average survival is around 35 to 60 months
5-year survival is around 35% to 60%
10-year survival is around 25% to 30%
Radiotherapy prolongs life in average
by 12 months or less after subtotal tumor resection, but makes no difference when the patient has undergone total resection

47. Prognostic factors are
functional status of the patient before the
surgery, the presence of calcification and
lack of anaplastic elements
Over 50% of recurrent tumors mutate in anaplastic oligodendroglioma
Low-grade astrocytic elements do not aggravate the prognosis
The prognosis of mixed oligodendroglioma with anaplastic astrocytic elements is the same as in anaplastic glioma

48. HISTOLOGICAL PROFILE Homomorphic cells with oval nuclei,
clear cytoplasm and defined cell membranes
Metallization at 70% to 90%
There may be suspicious astrocytic areas
(Mixed oligodendroglioma)
There may be typical anaplastic
changes (anaplastic oligodendroglioma)

50. 7) INTRACRANIAL EPENDYMOMA
Average age: 25 years
Percentage: 3% to 4% of gliomas
Localization:
4th cerebral ventricle. It may extend to cerebellopontine
angle
- In or near the third ventricle and the lateral ventricles
- 2/3 are located in the posterior fossa (most often in people
of young age)
1/3 is located in the supratentorial region (most often in adults)

51. Clinical profile Headache in more than 80%
Nausea and vomiting in 50% to 80%
Cerebellar disorders and oedema of the optic papilla
Average duration of symptoms is 4 months

52. Paraclinical examinations
- Head Computed Tomography :
- Mixed density, isodense or slightly hyperintense
Areas with calcification appear in more than 50% of cases
There may be cystic areas, especially in cerebellar localization
More than 80% contrast uptake
- Magnetic resonance imaging (MRI) of the brain :
- Punctated low intensity areas on T1-weighted sequences
due to calcification or cystic sections of the tumor
- Inhomogeneous gadolinium uptake

54. Treatment Surgical removal Radiotherapy is of considerable importance.
The dose depends on the location of the tumor,
the malignancy grade and the surgical outcome
In case of tumor recurrence, reoperation and/or
chemotherapy

55. Result 5-year survival is around 35% to 60%
1/3 to 2/3 will relapse if there are
anaplastic elements
Recurrences usually occur within 2
years and more than 90% are local
recurrences

56. The rate of anaplastic changes increases in supratentorial localizations There is no clear correlation between anaplastic changes and the patient's outcome Rare or absent is the possibility that the recurrent ependymoma presents anaplastic elements

57. HISTOLOGICAL PROFILE Homomorphic ependymal cells forming rosettes, or
pseudorosettes around the vessels

59. FACTORS THAT DETERMINE THE SURGERY
Tumor factors
The tumor as a space-occupying lesion
The localization (deep or superficial on vital
areas or not)
Its size
Its vascularization
Its composition (cystic or solid)
Its multiple localization

60. Patient factors - The neurological condition - Age - Surgical risks (bleeding diathesis, inflammations) - Risks associated with anaesthesia (Respiratory, cardiological, metabolic) - Previous treatment - Family history and patient's history