Primary brain tumors are a diverse group of neoplasms that can arise from different cells in the central nervous system. The most common primary brain tumor in adults is brain metastasis. Meningiomas are the most common non-malignant primary brain tumor, followed by pituitary and nerve sheath tumors. Gliomas account for 75% of malignant brain tumors, over half of which are glioblastomas. Primary brain tumors are classified and graded according to the WHO system, with grade I being low proliferative potential and grade IV being most malignant. Clinical features vary depending on tumor location but often include headaches, nausea, seizures, and focal neurological deficits.

1. PRIMARY TUMOUR OF
CNS IN ADULT
DR.PRAMOD MEENA
SR NEUROLOGY
GMC,KOTA

2. INTRODUCTION
• Primary brain tumours are a diverse group of neoplasm arising from
different cells of the central nervous system.
• It accounts for about 2% of all cancers with an overall annual
incidence of 22 per 1,00,000 population.
• Most common brain tumour in adults is Brain Metastasis.
• Meningiomas are the most common non-maliganant primary brain
tumour f/b Pituitary and nerve sheath tumours.
• Gliomas accounts for 75% of malignant brain tumours, in which more
than half are glioblastomas.

4. PRIMARY CNS NEOPLASMS BY LOCATION
• Meninges (36%)
• Cerebral hemispheres(31%)
• Sellar region(17%)
• Cranial nerves (7%)
• Brainstem, cerebellum(4%)
• Spinal cord/ cauda equina(3%)
• Ventricles(1%)
• Miscellaneous(1%)

5. BRAIN TUMOUR INCIDENCE BY AGE GROUP
CHILDREN( 0-14 YEARS OLD)
• Pilocytic astrocytoma,18%
• Neoplasm,15%
• Malignant glioma ,15%
• Astrocytoma ,11%
• Neuronal/ mixed glioneuronal,6%
• Ependymal ,6%
• Nerve sheath,5%
• Pituitary,4%
• Craniopharyngioma,4%

6. ADOLESCENTS (15-19 YEARS OLD)
• Pituitary,27%
• Pilocytic astrocytoma,10%
• Other astrocytoma,8%
• Neuronal, mixed glioneuronal,8%
• Nerve sheath,6%
• Meningioma,5%
• Germ cell,4%
• Ependymal,4%
• Embronal tumors,4%
• Glioblastoma,3%

7. ADULTS (20 + YEARS OLD)
• Metastatic,50%
• Primary,50%
• Meningioma,18%
• Glioblastoma,7%
• Pituitary, 7%
• Nerve sheath tumour,4%
• Other astrocytoma, 3%
• Lymphoma ,2%
• Oligodendroglioma, 2%
• All other, 7%
• Most brain tumours have male predominance except meningioma and low grade astrocytoma.

8. RISK FACTORS
Established
• Ionizing radiation
• Genetic predisposition
Not established
• Head trauma
• Electromagnetic field radiation
• Radiofrequency and cellular phones
• N-nitroso compounds
• Vitamin C and E
• Allergies/infection association
• Tea and coffee
• Occupational
• Tobacco, alcohol consumption.

9. CLASSIFICATION
• Brain tumors are classified according to the WHO CNS tumours
grading system.
• Previously, primary CNS tumours were defined on the basis of
histological criteria & assigned a grade ( from I to Iꓦ)
• In 2016, the classification was revised from the 2007 classification to
incorporate signature molecular genetic alterations to the classic
histology.

10. WHO Gradings:-only for Glioma
• WHO grade I – low proliferative potential. possible care with surgery
alone.
• WHO grade II- infiltrating but low in mitotic activity. Can recur and
progress to other grades.
• WHO grade III- Histologic evidence of malignancy( mitotic
activity),infiltrative,anaplastic.
• WHO gradeIꓦ- mitotically active, necrosis,rapid pre and post surgical
progression.

11. CLINICAL FEATURES
• Generalized
Headache
Nausea and vomiting
Syncope
Mental status and behavioral
changes
Seizure
• Focal
 Focal motor weakness
 Ataxia
 Seizure
 Aphasia
 Visual dysfunction

12. HEADACHE
• 50-70% patients
• Bifrontal and tension-like, with constant, dull pressure type
• Classic brain tumour headache occur in the early morning with
nausea and vomiting and improve over the course of the day
• Only occur in 5-17% of all brain tumour patients, 42% of whom have
posterior fossa tumour
• More common in brain metastases and glioblastomas (90%).

13. Diagnostic investigations
• MRI Brain with Contrast is the investigation of choice.
• Diffusion-weighted imaging, diffusion tensor imaging, MR perfusion &
MR spectroscopy are used to better characterize the tumour
cellularity, vascularity and metabolism respectively.
• Can distinguish tumour, from non neoplastic processes,including
treatment effect.
• Surgical biopsy

14. CT HEAD:-
Intra axial tumours- usually low attenuation
high attenuation areas within a tumour
calcification, hemorrhage and lymphoma
Extra axial: bone erosion and hyperostosis
MRI Brain:-
TIWI: low signal intensity
T2WI/ FLAIR: High signal intensity



15.  LOW SIGNAL INTENSITY IN T2WI:
1.CNS Lymphoma
2.PNET
3.Metastasis( melanoma)
4.GBM (less common)
5.Meningioma( less common)
 ENHANCEMENT: Almost all tumors except
Low grade glioma (WHO II & III)
CYSTIC NON-tumoral lesions:
1. Dermoid cyst
2. Epidermoid cyst
3. Arachnoid cyst

16.  Homogeneous enhancement seen in:
1.Metastases
2.Lymphoma
3.Germinoma And Other Pineal Gland Tumours
4.Pituitary Astrocytoma And Hemangioblastoma
5.Ganglioglioma
6.Meningioma and schwannoma
 Patchy enhancement seen in:
1.Metastases
2.Glioblastoma multiforme
3.Radiation necrosis

17. Ring enhancement:-
Metastasis
High-grade Glioma
Diffusion restriction:-
CNS Lymphoma
Oligodendroglioma
MR Spectroscopy:-
Decreased NAA, increased choline ( Ch/NAA ratio ˃1.3)

39. Mixed Neuronal-Glial Tumours-
Ganglioglioma
• Sezure are the most common manifestation.
• MC location-supratentorial(temporal>frontal)
• Children and young adults
• 30-50% calcification
• Presenting as cyst-mural enhancing nodule
• Gross total resection results in survival ranging from 7 to 17 years.
• Adjuvant irradiation for incompletely resected or anaplastic progression (survival
of 3years or less)

41. CHOROID PLEXUS TUMOUR :
• Includes papilloma and carcinoma
• Tumour of childhood
• In adults it account for only 0.2% of all intracranial neoplasm.
• Located in
1. Lateral ventricle(mc)
2. the cerebello-pontine angle
3. fourth ventricles.

43. Meningeal tumours- Meningioma
• Most common primary intracranial tumours
• Older adult
• Incidentally found asymptomatic meningiomas( lacking mass effect or
compression of a venous sinus)
• When seizure occur ,tumour grow or focal signs emerge
• Surgical can be curative ,especially in meningioma overlying the
hemisphere.

47. PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA
• An uncommon variant of Extranodal Non-Hodgkin Lymphoma.
• Involves the Brain (periventricular), leptomeninges, eyes or spinal
cord without evidence of systemic disease.
• Most cases are diagnosed in patients between 45 and 65 year of age,
median age( fifth decade) ( non-HIV related PCNSL)
• Homogenous enhancement and diffusion restriction.
• The most notable risk factor is immunodeficiency
• Highly aggressive tumour.
• Left untreated, most patients succumb within 6 months.

49. • Methotrexate- based chemotherapy given in high doses (HD MTX
,above 3.5g/m2 )
• F/b Leucovorin rescue has been shown to be the single most effective
treatment for PCNSL.
• For PCNSL in AIDS patients, WBRT has been the standard treatment
resulting in poor and non durable response.

53. Conclusion
• Primary brain tumors remain difficult and challenging disease to
manage despite substantial progress in understanding their genesis.
• Treatments and better outcomes for primary brain tumors have long
lagged behind those of other tumours.
• Combinational regimens will be required to achieve a broad and
durable antitumor benefit.
• New advances in cell engineering technologies and infusion of exvivo
prepared immune cells are promising strategies.
• The present challenge is to translate this better understanding of the
pathophysiology into effective therapies.

54. REFERENCES
• Bradely′s Neurology in clinical practice, 8th edition.
• Osborn′s Diagnostic Brain Imaging, 3rd edition.
• Louis DN, Ohgaki H, Wiestler OD CW.(2016) WHO classification of Tumours
of the central nervous system( revised 4th edition).WHO Lyon ,2016
• Ostrom QT , Gittleman H,LiaoP, et al.CBTRUS stastical report.
• Primary brain and other central nervous system tumours diagnosed in the
united states in 2010-2014.neuro Oncol 2017;19:1-8
• Weller M, van den Bent M, Tonn jc,et al.European Association for Neuro-
oncology(EANO) guideline on the diangnosis and treatment of adult
astrocytic and oligodendroglial gliomas.Rev Lancet Oncol 2017;18:315-29.
• Up TO Date