The document provides a comprehensive overview of brain tumors, discussing their epidemiology, classification, anatomical considerations, clinical features, and treatment modalities. It emphasizes the differences in tumor incidence between genders and age groups, detailing the types of brain tumors, including primary and secondary, and their histological characteristics. Recent advances in treatment approaches such as surgery, radiation therapy, and chemotherapy are also highlighted, reflecting on the multidisciplinary strategies required for effective management of these conditions.

1. Brain Tumours
Dr. Fakir Mohan Sahu
SR MCh Neurosurgery
Dept of Neurosurgery
AIIMS Bhubaneswar

2. Learning Objectives
• Epidemiology and incidence
• Anatomical consideration and location
• Classification of brain tumours
• Clinical features
• Diagnostic imaging
• Individuals tumours
• Treatment modalities
• Recent Advances

3. Introduction
• A wide variety of tumors affect the CNS (Brain + Spinal cord)
• Primary benign and malignant tumors arise from the various elements of the CNS,
including neurons, glia, and meninges.
• Tumors metastasize to the CNS from many primary sources.
• Presentation varies widely depending on relevant neuroanatomy.
• Prognosis depends on histology and anatomy
• Team approaches to CNS tumors, as patients may require a combination:
Surgery,
Radiation Therapy
Chemotherapy and Research Protocol Enrolment.

4. Epidemiology of Intracranial tumour
• In general, primary brain tumors is higher in whites than in blacks
• Males are more likely to be diagnosed with brain tumors than females-( 1.5:1 )
• Meningiomas and pituitary adenomas are slightly more common in women than in men.
• Mortality is higher in males than in females.
• Brain tumours are responsible for 2% of all cancer deaths.
• The incidence varies with age.
In children CNS tumours comprise 20 % of all childhood malignancies.
Peak at 2 years followed by a decline for the rest of the first decade.
• The incidence then slowly increases, peaking at 20 per 100 000 in late adulthood.

5. Anatomic consideration and location of tumours
The brain consists of
• The Cerebrum - 2 Large
Cerebral Hemisphere
4 major lobes
• The Cerebellum
• Brainstem
• Midbrain
• Pons
• Medulla

6. Location
• In adults supratentorial tumours
out number posterior fossa
tumour by a ratio of 7 to 3
• But in children this ratio is
reversed and posterior Fossa
tumours are the most common.

7. Classifications
• Intracranial tumour can be classified in different ways:
Paediatric versus adult, by cell of origin
By location in the nervous system.(Supratentorial/ Infratentorial/
Intraventricular)
Classification of brain tumour (according to cell of origin)
Neuroepithelial tumours 50%
Metastatic 15%
Meningioma 15%
Pituitary tumour 8%
Others

8. Primary Tumour
Primary intracranial tumour can occur at any age, it is
helpful in deferential diagnosis to know that certain
tumor occur mainly in certain age groups.
BRAIN TUMOUR
Secondary Tumour
These affect mainly the middle aged and elderly, with the
exception of secondary neuroblastoma which occurs
mainly in children.
Classification

9. CLASSIFICATION OF INTRA CRANIAL TUMOURS:
There are several ways of classifying brain tumours:
primary versus secondary
intraxial ( arising from the brain parenchyma) versus extra
axial ( arising from tissue covering the brain such as dura)
and
various regional
classification
> Supratentorial
> Infratentorial
> Intraventricular
> Pineal region
> Sellar region tumours. Contd ..

10. Astrocytomas
Oligodendroglioma
Ependymal tumours
CLASSIFICATION ACCORDING TO HISTOLOGY
Primary brain tumours are subdivided into two basic groups:
Tumours of neuroglial origin (Glioma)
Non - glial tumours that are specified by a combination
of putative cell origin and specific location.
Glial tumors (gliomas)
Contd ..

11. NONGLIAL TUMOURS
Neuronal and mixed neuronal- glial tumours
Ganglioglioma
Gangliocytoma
Meningeal and mesenchymal tumours
Meningioma
Hemangiopericytoma
Hemangioblastoma
Fibrous histiocytoma Contd .
.

12. NONGLIAL TUMOURS
Pineal region tumours
Pineocytoma
Pineoblastoma
Pineal cell tumours
Choriocarcinoma
Teratoma
Germinoma
Germ cell tumours
Contd ..

13. Nonglial tumours
Other cell tumours
Benign pineal cysts
Astrocytoma
Embryonal tumours
Neuroblastoma
Primitive neuroectodermal tumours ( PNET)
Cranial and spinal nerve tumours
Schwannoma
Neurofibroma

14. NONGLIAL TUMOURS
Hemopoetic
neoplasm's
Lymphoma
Leukemia
Plasmacytoma
Pituitary tumours
Contd ..

15. NONGLIAL TUMOURS
Cysts and tumour like lesions
Rathke cleft cyst
Dermoid cyst
Epidermoid cyst
Colloid cyst
Enterogenous cyst
Neuroglial cyst
Lipoma
Hamartoma
Contd .
.

16. NONGLIAL TUMOURS Contd.
Local extensions from regional
tumours
Craniopharyngioma
Paraganglioma
Chordoma
According to location
Intra axial
Extra axial

17. Points Intra axial Extra axial
Within brain
parenchyma.
Outside brain
parenchyma
Yes
Location
Contiguity with bone /
flax
Bony changes
CSF space
Usually not
Usually not
Effaced
Yes
Often widened
Corticomedullary buckling No Yes
GM / WM junction Destruction
Vascular supply
Internal carotid
artery
Preservation
External carotid
artery

18. Supratentorial
• Meningeoma
• Dermoid
• Epidermoid
• Pitutary adenoma
• Pineal region tumour
• Craniopharyngeoma
• Chordoma

19. Infratentorial
• Brainstem glioma
• Cerebellar astrocytoma
• Medulloblastoma
• Ependymoma
• Meningioma
• Hemangioblastoma
• Dermoid
• Acoustic neuroma
• Meningioma
• Dermoid
• Chordoma
• Glomus jugular tumour

20. OTHER
CLASSIFICATION
Intraventricular tumour
Ependymoma
Choroid pluxus tumor
Colloid cysts
Meningioma

21. CLASSIFICATION – ACCORDING AGE
GROUP
5-15
YEARS CLASSIFICATION
0-5 Brain Stem Glioma, Optic Nerve Glioma
Medulloblastoma, Cerebellar Astrocytoma,
Craniopharyngma, Choroid Plexus Papiloma ,
Pinealoma.
15-30
30-60
60+
Ependymoma
Glioma, Meningioma, Acoustic neuroma,
Pitutary Tumour, Hemangioblastoma
Meningeoma, Acoustic Neuroma,
Glioblastoma

22. WHO CLASSIFICATION
CLASSIFICATION
Pilocytic astrocytoma
SGCA(subependymal giant cell astrocytoma)
Low grade astrocytoma
Anaplastic astrocytoma
GRADE
Grade 1
Grade 2
Grade 3
Grade 4 Glioblastoma multiforme

23. FEATURES OF LOW GRADE
GLIOMA
Age – Younger age group 20- 40 yrs
Incidence – 10- 20% of astrocytoma
Location –
Histology-
cerebral hemisphere
frontal and parietel lobe
temporal lobe
low grade malignancy
Presenting Symptom - Seizure

24. IMAGING STUDY LOW GRADE GLIOMA
CT
NECT : Iso/hypo
CECT : Little or no enhancement

25. IMAGING STUDY LOW GRADE GLIOMA
MRI
T1 : Iso/Hypointense
T2 : Homogenously
hyper

26. ANAPLASTIC ASTROCYTOMA
It usually occurs in the middle aged patients
Incidence- 20- 25%
Locations: cerebral hemispheres
frontal and
temporal lobe
Histology- malignant
Presenting Symptom- Seizure, focal neurological deficit

27. CT
IMAGING STUDY ANAPLASTIC ASTROCYTOMA
NECT : Iso/hypo In homogenous mixed density
CECT : Enhance strongly, inhomogenously

28. IMAGING STUDY ANAPLASTIC ASTROCYTOMA
MRI
T1: Hypo to iso intense
T2 : Heterogenously Hyperintense
As typically enhance strongly
but non uniformly following
contrast administration.
Irregular rim enhancement is
common

29. GLIOBLASTOMA MULTIFORME
Half of all astrocytoma are GBM. It is most common
supratentorial neoplasm in adult. The most common primary
brain tumour, it is also the most malignant astrocytoma
Incidence –
Age-
Locations-
Presenting symptom-
deficit,
40-50%.
> 50yrs.
cerebral hemisphere, Frontal and
temporal lobe, White mater
Seizure, Focal neurological
stroke like syndroms

30. IMAGING STUDY
Enhances strongly, inhomogenously.
Ring enhancing lesion – due to increased
cellularity and neovascularity.
Area of central necrosis shows hypodensity
Imaging study shows ‘multiforme’ appearance
CT
NECT : In homogenously mixed density

31. MRI
T1: T1 weighted image shows mixed signal mass with
necrosis or cyst formation and thick irregular wall.
Marked but in homogenous contrast enhancement is
present in majority of glioblastoma multiforme. These
tumours are hihgly vascular, haemorrhage of different
ages are often present.
T-1 T-1 C T-1 C

32. MRI
T2: T2- weighted image shows very heterogenous mass with
mixed signal intensity. Central necrosis is the hall mark.
Haemorrhage , necrosis, oedema are present in GBM
Angiograph
y
Alarge mass with striking tumours blush, Contrast stasis
and pooling in Bizarre vascular channel is typical

33. IMAGING STUDY Contd.
Spread
Through white mater
Sub ependymal seedling
Through CSF
Rarely through haemtogenous route
Extra cerebral metastasis- Lung, Liver, Bone

34. MRI
Sharply defined macrocystic mass
Mural nodule easily appreciate with
contrast enhancement
PILOCYTIC ASTROCYTOMA IMAGING STUDY

35. OLIGODENDROGLIOMA
Arise from a specific type of glial cell- Oligodendrocyte. These
are typically unencapsulated but well circumscribed focal
white matter tumours that may extent into the cortex and
leptomeninges. Foci of cystic degeneration common Hge,
necrosis uncommon
Incidence -
Age distribution-
Peak age
Location
-
-
5- 10% of gliomas
4th to 5th decade
35- 45 yrs.
85% supratentorial
Cerebral hemisphere- mostly
frontal lobe

36. IMAGING STUDY-
OLIGODENDROGLIOMA
CT
NECT- Prominent mass of calcification. Partially calcified
mixed density hemispheric mass that extends peripherally to
the cortex.
CECT- Mild to moderate contrast enhancement occurs

37. MRI
Heterogenous signal intensity due to calcifiacation
T1W iimage shows mixed hypo or iso intensity
T2W image shows hyper intense foci
Absent to slight enhancement is typical
T-1 T- 1 C T- 2
IMAGING STUDY-
OLIGODENDROGLIOMA

38. EPENDYMOMA
Ependymomas are tumours of the young and are third
most common intracranial tumour ofchildren
Age distribution-
Incidence-
1-5 yrs.
2-8% of gliomas
15% of pediatric brain tumour
Location- 60% infratentorial more common in children .
40% supratentorial more common inadult.
4th ventricle, C- P angle, in or near 3rd ventricle

39. IMAGING STUDY- EPENDYMOMA
CT
NECT-
CECT-
Mixed density, isodense or slightly hyperdense
Fine calcification seen in approximately 50% of the
patients.
May have cystic areas
More than 80% contrast enhancement occurs

40. MRI
T1- Heterogenous signal intensity markedly hypointense area
due to calcification
In homogenous enhancement with gadolinium
T2- Iso to hyper intensity
Histological feature shows uniform ependymal cells in pattern of
rosettes, canal or perivascular pseudorosettes

41. CHOROID PLEXUS PAPILLOMA
Tumours of choroid plexus are rare, accounting for 0.4-
0.6% of all intracranial tumour
Age distribution- > 85% occurs in children
Location In children MC site lateral ventricle
In adult most of the choroid plexus
papilloma occurs in 4th ventricle

42. IMAGING STUDY CHOROID PLEXUS
PAPILLOMA
CT
NECT
CECT
Iso or hyperdense, 3/4th hyperdense
heterogenous contrast enhancement

43. MRI
T1 weighted image shows- Predominently isointense
Intensely contrast enhancement
occurs
T2 weighted image shows- Iso to hyperintense,
occasionally signal void from the vascular pedicle
IMAGING STUDY CHOROID PLEXUS
PAPILLOMA

44. PINEAL TUMOUR , Cont
the incidence of
The pineal region tumours are rare tumour
which is 1% of all intra cranial tumour.
Gemcell tumour
Pineal cell tumour
Germinoma
Teratoma
Embryonal carcinoma
Choriocarcinoma
Pinealoblastoma
Pinealocytoma
Types of pineal region tumour are as follows

45. SELLAR/SUPRASELLAR MASSES
The sellar region is an anatomically complex area
composed of the bony sellaturcica, pituitary gland, and
adjacent structures
Pituitary adenoma
Older classification
Chromophobic
Acido philic
Basophilic
Mixed
New classification
Pituitary microadenoma ( size
<10mm)
Pituitary macroadenoma (size

46. IMAGING STUDY
X-ray
expansion of sellar cavity
thining of bony cortex
ballooning of sella
CT
Large, homogenously isodense, rounded midline mass

47. MRI
T 1 weighted image shows hypointense
T 2 weighted image showshyperintensity
Extension is better visualized after contrast
Both CT and MRI show strong contrast enhancement with
some what inhomogenously

48. MENINGEAL AND MESENCHYMAL TUMOUR
Meningiomas
Malignant mesenchymal tumour
Hemangiopericytoma
Hemangioblastoma
Meningiomas
Meningiomas are most common nonglial primary brain tumour
Most common extra axial tumour ( 13- 18%)
Age – adult tumour 40- 60yrs
Sex- more in female
Cytogenetics- chromosome 22 is important for pathogenesis
of meningioma

49. Location meningioma
Cerebral convexity 32- 45 %
Parasagital 26%
Sphenoid ridge
Juxtra sellar
20 %
10 %
olfactory groove 10 %
Posterior fossa 10 %
Tentorium
Pineal region
Others optic nerve sheath, intravetrricular

50. IMAGE STUDY
X-ray
Hyperostosis
Erosion
Enlarged vascular
Calcification
Pneumosinus dilatans

51. IMAGE STUDY
CT
70% to 75% hyperdense
20% to 25% calcified
90% enhance strongly , uniformly
10% to 15% cystic areas
60% peritumoral edema
Hemorrhage
rare
Area of haemorrhage, necrosis, cyst formation are common
which appear as hypodense within the tumour

52. IMAGE STUDY
Angiography
Dual vascular supply common
Sunburst of enlarged dural feeders in tumour
Extension
Into the suprasellar cystern forming the figure of eight( 8 )
Elevate and compress the optic chiasma and 3rd ventricle
Laterally into the cavernous sinus
May encase the ICA or narrow the vessels

53. Common CPA
masses
- Vestubular schwannoma ( acoustic neuroma)
- Meningioma
- Epidermoid
- Other schwannoma
- Less com.
- Arachnoid cyst
- Metastases
- Vascular
- Lipoma
- Dermoid.
CEREBELLOPONTINE ANGLE ( CPA) CISTERN MASSES

54. MEDULLOBLASTOMA
Most common malignant pediatric brain tumour.
Incidence: 15- 20% of intracranial tumour in children.
Male: Female 2:1.
Age: most in 1st decade. 75% in 4- 8 years.
Site: 75% arises in the cerebellar vermis mostly in midline,
in the apex of 4th ventricle.
25% arises in lateral cerebellum.
Highly radiosensitive and moderately chemo sensitive.
Metastasis occur early in the CSF.
Prognosis is very poor

55. CRANIOPHARYNGIOMA
Craniopharyngiomas arise from the squamous epithelial rests
along the involuted hypophyseal Rathke’s duct.
Incidence: 3- 5% of primary brain tumour.
50% of pediatric brain tumour.
Age: > 50% in children, peak between 8-12 years.
Location: 70 % combined suprasellar and intrasellar
Imaging study
CT scan of brain-
90% partially cystic,
90% calcification present,
90% nodular or rim enhancement occur
MRI of Brain
Variable signal, most common is hypointense in T 1 weighted
image and hyperintense in T2 weighted image

56. INTRACRANIAL METASTASES
Representing 1/ 4th to 1/ 3rd of all brain tumour.
Common:
Skull
Leptomeninges
Parenchymal (most common).
Less common:
Dural
Pial
Sub pial
Parenchymal metastases:
Location – any where but most common in cortico medullary
junction ( grey mater- white mater interface).

57. INTRACRANIAL METASTASES
Pathology
Welldefined circumscribed nodule of variable size
May be solid partially cystic, filled with mucinous material,
necrotic material, haemorrhagic fluid .
Imaging Study
CT:
NECT- mostly isodense lesion / hyperdense lesion-
Example- Thyroid carcinoma, Lung carcinoma, choriocarcinoma,
malignant melanoma, sarcoma

58. INTRACRANIAL METASTASES
Cystic metastasis
Mucin producing tumour adenocarcinoma arising from stomach,
small and large intestine, pancreas, ovary, breast cancer
Cystic and calcified metastasis
Rare- breast carcinoma, lung cancer.
CECT: Most enhance strongly, both solid and ring shaped
pattern are noted
MRI
T 1 weighted image- shows variable features most non
haemorrhagic tumour slightly hyper intense.
Some non haemorrhagic tumour – hyper intense

59. General
Consideration

60. Surgicalmanagement:Craniotomy+ Excision
Approaches
Craniotomy:- flap of bone is cutand
reflected.
- If necessary, combined with either a
stereotactic frame
- or preferably an image guided
system(frameless, steriotaxy) to give
accurate lesion localisation

61. Operative procedure:
Thesubsequent procedure
Biopsy Partial tumour removal Internal decompression Complete removal
Depends on the nature of the tumour &site.
Primary malignant tumour :complete removal of tumour is not possible due to its
infiltrative nature. So operation is restricted to -biopsy
-Tumourdecompression
Complete removal is done for
-Meningioma
-Craniopharyngioma

62. Radiotherapy
Aim :toprovide highest possible dose
tothe specificregion, while minimal
irradiation toadjacent normal brain.
Indication: In malignant tumour:
- malignant astrocytoma
- metastasis
- medulloblastoma
- germinoma
In benign tumours
- pituitary adenoma
- craniopharyngioma

63.  Malignant astrocytoma:
 -nitrosoureas are most effectivedrug
 commonly used treatmentforrelapsepatient
 Low gradetumour or benign tumour:
 chemotherapy has limitedvalue
 Medulloblastoma:
 respond totreatmentbut value of treatmentof patient survival – is unclear.
 Primary germ cell tumour & primary cerebral lymphoma:
chemotherapy has a role.
Chemotherapy

64. Prognostics Variables
For each tumour entity, combinations of parameters
WHO grade
Clinical findings- age/ neurologic performance Status
Tumour location
Radiological features - contrast enhancement
Extent of surgical resection
Proliferation indices
Genetic alterations

65. Recent advances
• Neuro-navigation
• Stereotactic surgery
• Endovascular embolization
• Endoscopic Surgery

66. Thank
You