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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. WHO CLASSIFICATION OF NEUROEPITHELIAL TUMORS ( World Health Organization) 1. Astrocytic tumors
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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
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
4. Poorly differentiated tumors and embryonic stem cells Glioblastoma Medulloblastoma 5. Tumors of pineal cell origin Pinealoma Pinealoblastoma 6. Neuronal tumors Gangliogloioma Gangliocytoma Neuroblastoma
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
Grade 3Many cells appear as astrocytesPleomorphism Few mitotic figuresNecrosis frequentlyPartial endothelial proliferation in vesselsGrade 4Few normal astrocytes appearPleomorphism prevailsMany bizarre mitosesNecroses frequentlyEndothelial proliferation in vessels prevails
ASTROCYTIC TUMORS 1) PILOCYTIC ASTROCYTOMA Average age: 13 years Percentage: 2% of gliomas Localization: - Cerebellum / strain (61%) - Optic chiasm / hypothalamus (28%) - Cerebral hemispheres (11%)
Clinical profile - Chiasmal tumors : visual deficits, endocrinological dysfunctions, symptoms of hydrocephalus - Cerebral hemispheres tumors : headache, epileptic attacks, motor deficit
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
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
Result • 81% survive for 10 years • after subtotal resection of tumor and • radiotherapy • 54% survive for 20 years • after subtotal resection of tumor and • radiotherapy
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
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%)
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%)
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.
Treatment • Surgical removal • Postoperative radiotherapy is • controversial. • - Chemotherapy is contraindicated
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.
86% of astrocytomasthat relapseare already anaplasticPrognostic factors areage, physical condition ofthe patient and the extent of surgical resection
HISTOLOGICAL PROFILE • Moderate polycytosis • The nuclei may appear • large but without any significant • pleomorphism • No vascular reproduction • No necrosis
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
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
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
Treatment • Surgical removal • Postoperative radiotherapy • depends on the extent of tumor resection • In case of recurrence • reoperation, chemotherapy, • brachytherapy and radiotherapy are recommended
Result • 2-year survival is around • 40% to 50% • 5-year survival is around 18% • after surgery and radiotherapy • and chemotherapy
Prognostic factors are age, functional status of the patient and the residual tumor • 45% of tumors that relapse are already higher grade glioma
HISTOLOGICAL PROFILE • Moderate polycytosis • Moderate pleomorphism of cells and • of nuclei • Local anaplastic changes • Necrosis points
4) GLIOBLASTOMA MULTIFORME (GBM) • Average age: 50-60 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
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
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
Treatment • Surgical removal • Postoperative radiotherapy depends on • the extent of tumor resection • In case of recurrence • reoperation, chemotherapy, brachytherapy and radiotherapy are recommended
Result • - 2-year survival is around 10% • - 5-year survival is around 5.5% • 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
Prognostic factors are age, functional statusof the patient and theresidual tumor aftersurgery and radiotherapySome neurosurgeons recommend onlybiopsy and adjuvanttherapy for high malignancysupratentorial tumors
HISTOLOGICAL PROFILE • Polycytosis • Pleomorphism of cells and • of cytoplasm • Often vascular hyperplasias • Necroses frequently
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
Clinical profile - Epileptic attacks constitute > 50% - Headache at 30% to 78% - personality disorders, visual disturbances, and focal deficits (in the absence of seizures)
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
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
Result • - Average survival is around 35 to 60months • 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
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 anaplasticoligodendroglioma • 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
HISTOLOGICAL PROFILE • Homomorphic cells with oval nuclei, • clear cytoplasm and definedcell membranes • Metallization at 70% to 90% • There may be suspiciousastrocytic areas • (Mixed oligodendroglioma) • There may be typical anaplastic • changes (anaplastic oligodendroglioma)
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)