This document provides an overview of central nervous system (CNS) tumors. It begins by classifying tumors based on origin and nature. It then discusses the occurrence, clinical manifestations, syndromes, and general clinical features of CNS tumors. Specific pediatric and adult tumor types are also described, along with their characteristics, treatment approaches, and prognoses. Finally, the document briefly discusses spinal tumors, including types, clinical presentation, diagnosis, and differential diagnosis.

1. Man Bahadur Paudyal

2. Introduction I
Classification:
A. Based on origin of tumor
1. Primary
2. Secondary (Metastatic)
B. Based on nature of tumor
1. Benign: well-encapsulated, slow-growing
non-infiltrative, low tendency to invade
2. Malignant: non-encapsulated, rapid-growing
highly infiltrative.

3. Introduction II
Occurrence
CNS Tumor: 10% of all tumors
Brain (80%) Spinal Cord (20%)
Ultimate outcome: increased ICP
Mass effect
tumor perifocal edema intratumoral hge
Direct compression
infiltration CSF pathway obstruction
Focal effects
CN deficits

4. Clinical Manifestation
Depends on the location of the tumor.
With supratentorial tumors:
1. Seizure
2. Mental changes (memory loss, behavior changes)
3. Focal deficits (visual field deficit, paralysis)
With infratentorial tumors:
1. CN palsies
2. Cerebellar signs (ataxia, dysmetria, tremor,
nystagmus, diadodiskinesia)
3. Obstructive hydrocephalus

5. Clinical Syndromes
Frontal lobe syndrome
1) Mental/ personality changes
2) Incontinence
3) Speech disorders
4) Paralysis
Temporal lobe syndrome
1) Aphasia
2) Psychomotor seizures
3) Visual field changes (hemianopia)

6. Parietal lobe syndrome I
I. With dominant hemisphere
1) Gerstman’s syndrome
a) agraphia without alexia (can read but not write)
b) left to right confusion
c) digital agnosia ( can not name fingers)
d) acalculia (can not do simple calculation)
2) Language disorder
3) Tactile agnosia
4) Ideomotor apraxia

7. Parietal Syndromes II
II. With non-dominant hemisphere
1) Topographic memory loss
2) Anosognosia
3) Dressing apraxia
III. With either
1) Focal seizures
2) Agnosia
3) Sensory changes
4) Dyslexia

8. General Clinical Manifestation
1. Severe progressive headache, worst in morning
2. Vomiting, projectile, without prenauseate phase
3. Seizures (generalized/focal)
4. Altered sensorium
5. Changes in mentation
6. Abnormal sensations
7. Increased ICP
8. Papilledema
9. Central herniation with brainstem dysfunction
10. Compression of brain parenchyma/blood vessels/CSF path
(1) Ischemia (2) Infarction (3) Hydrocephalus
(4) Edema (5) Hemorrhage
11. Suture separation in children < 5 yr
12. Bony erosion

9. Classification of CNS Tumor
In adults, the majority are supratentorial and
of metastatic type; whereas in children,
infratentorial tumors are more common.

10. Common Pediatric Intracranial
Tumors
I. Medulloblastoma
II. Ependymoma
III. Cerebral Astrocytoma
IV. Cerebellar Astrocytoma
V. Brainstem Glioma (BSG)
VI. Craniopharyngioma (CP)

11. Medulloblastoma
Most common malignant pediatric brain tumor
(15 ~ 20%)
Arises from cerebellar vermis & apex of IV
ventricle roof
Predispose to early obstruction of CSF pathways
CSF seedlings
CT-scan: sold midline enhancing lesion
MRI: Banana sign
Highly radiosensitive/ moderately chemosensitive

12. Treatment
Surgery Suboccipital craniectomy+Excision ±
Shunt
Ventriculostomy ⇒ Definitive surgery
Postoperative radiation/ chemotherapy
Prognosis
Poor prognosis Younger age < 4 yr
Dissemination
Unable to perform total
resection
Histological differentiation
Without treatment, survival ≤ 1 ~ 2 yrs
With treatment, 5 & 10 yr survival 56% &
43%

14. Ependymoma
Usually benign but may be inoperable due to location
Intracranial location is usually infratentorial and in spine,
especially in filum teminalis (myxopapillary)
May seed along CSF pathways/ occur along neuraxis
CT/MRI: commonly calcified, inhomogeneous on T1WI and
exophytic component is high signal in T2WI
Treatment
Surgery & postoperative radiation
Prognosis
Worse due to propensity to invade obex
5 yr survival 41%

15. Cerebral Astrocytoma
Types:
Low gr ( I + II ): less malignant better prognosis
High gr ( III+IV ): highly malignant poor outcome
Usually involve:
Frontal Basal ganglia Thalamus
Midline structures
Butterfly glioma: arising from corpus callosum with
bifrontal lobe involvement
Arises from neuro-ectodermal tissue
Treatment: Surgery/Biopsy
Postoperative radio/chemotherapy
Prognosis: Average survival < 1 yr in high grade

16. IV. Cerebellar astrocytoma
 Usually benign & cystic
 Usually present during 2nd decade
 Usually involves pons, midbrain & medulla
 Does not seed along CSF pathway
Pilocytic type
occur in younger age & have better prognosis
Radiographically, cystic with mural nodule
Pathologically, compact/loose astrocytes with
Rosenthal fibres
Treatment: Surgery + Postoperative radiotherapy
Prognosis: Long-term survival possible with combined

18. V. Brainstem Glioma (BSG)
Slow-growing & highly malignant with poor
prognosis
Usually presents with multiple CN palsies & long
tract signs
Treatment: Surgery + postoperative
radiotherapy
Prognosis:
With RXT, survival 4 yr
Without RXT, only 1 yr

20. Craniopharyngioma (CP)
 Benign suprasellar lesion
 Arises from rakhte’s remnants
 May be prechiasmatic/retrochiasmatic
 Causes pituitary dysfunction, visual field deficits
 CT/MRI: almost all have solid & cystic components
Spoke & Wheel appearance
Treatment:
Surgery: Subtemporal/subfrontal/transsphenoidal
Postoperative XRT
Prognosis: Favorable if totally resected

23. Common intracranial tumors
in adults
I. Glioma
II. Meningioma
III. Vestibular Schwanoma (Acoustic neuroma)
IV. Pituitary Adenoma
V. Miscellaneous tumors

24. I. Glioma
 All tumors that arise from neuroglial cells
 Consists of (1) Astrocytoma (2) Oligodendroglioma
Oligodendroglioma (Oligo)
1. Slow-growing & often calcified
2. Frequently presents with seizures
3. Occurs in cerebral hemispheres
4. Fried egg appearance in LP microscopic view

25. Meningioma
Usually benign, slow-growing, frequently calcified & extra-
axial
Commonly seen in middle-aged women
Arising from arachnoid layer
Usually located supratentorial along falx,
convexity/sphenoid
Tendency to compress than infiltrate brain parenchyma
Classic pathological findings is psammomna bodies
Usually cured if completely removed which is usually
impossible
May be highly vascular (angioblastic)

26. CT-scan:
Homogeneously enhancing lesion
with broad base attachment along dura
usually with little/ no perifocal edema
MRI: Dural tail
Treatment: Surgery & Postoperative XRT
Prognosis:
Favorable with total resection, maybe
recurrent
In totally resected case, recurrent rate 15%
With partial resection upto 85% after 5 yr

29. Pituitary AdenomaArises from anterior part of pituitary (Adenopypophysis)
Type: Microadenoma < 1 cm Macroadenoma
Functional Non-functional
Causes
Compression of optic chiasma ⇒ bitemporal hemianopia
Compression of cavernous sinus⇒ CN palsy(III, IV VI, V1,2)
Endocrinologic disturbances
ACTH Cushing’s disease
PRL Amenorrhea-galactorrhea syndrome
GH Gigantism (Children) Acromegaly (adult)
Apoplexy:
Abrupt onset of neurologic deterioration due to expanding mass as
result of hemorrhage
Causes visual deterioration, ophthalmoplegia, reduced MS & pituitary
hypofunction

33. Acoustic SchwanomaBenign, usually unilateral or maybe part of MEN (bilateral)=
NF2
Arises from vestibular branch of 8th CN
Causes compression than infiltration
Classic signs: insidious/progressive
Early: Decreased hearing High-pitch tinnitus
Dizziness Dysequilibrium
Late: Hemifacial numbness (CN V palsy)
Facial asymmetry, lidlag ( CN VII palsy)
Pathology: benign with Antoni A & B
CT-scan: erosion/enlargement of IAC (bone window)
Ice cream cone
MRI: Round/oval enhancing lesion centered on IAC
Treatment: Surgery Retrosigmoid, Translabyrinthine,
Subtemporal

34. Miscellaneous Tumors I
Colloid cyst
Classically occur in III ventricle blocking Foramen of Monro
Causes obstructive hydrocephalus
Slow-growing, benign lesion
Treatment: Surgery( Trancallous/Transcortical Vs Endoscopic)
VP Shunt
Hemangioblastoma
Most common primary intra-axial tumor in adult posterior fossa
May be part of von Hippel Lindau disease
May be associated with erythrocytosis
Cerebral Lymphoma
CT/MRI: homogeneously enhancing lesion in central gray matter
Fluffy cotton ball appearance
May present with multiple CN palsies
Extremely responsive to steroids ( ghost tumors)
Diagnosis highly likely if uveitis is present

36. Miscellaneous Tumors II
Chordoma
Benign, highly recurrent, slow-growing, locally aggressive
Generally radio/chemoresistent
Arises from remnants of primitive notochord
Cranially, found in sphenooccipital region (clivus) & in
sacrococcygeal region in spine
Chordosarcoma: Arises from paramedial region
Cerebral Metastasis
Most common brain tumor seen clinically
Sources:
Adults: Lung, breast, kidney(, GI, melanoma, thyroid
Children: Neuroblastoma, rhabdomyosarcoma, Wilm’s
High grade glioma, medullo, ependymoma, pineal tumor
Location: parenchyma/leptomeninges
 80% in cerebral hemispheres, mostly parietal lobe

37. Pseudotumor Cerebri
(Benign/Idiopathic Intracranial
Hypertension)Increased ICP ⇒ papilledema without intracranial mass,
hydrocephalus or normal CT/MRI
Usually self-limited, easily recurring, chronic
Preventable cause of blindness from optic atrophy
Treatment
Fluid/salt restriction
Diamox 250 mg PO q8
Lasix up to 160 mg/d
Steroid Dexamethasone 4 mg PO q6
Prednisolone 40 ~ 60 mg PO qd
Surgery Serial LP, LP shunt
Optic N sheath decompression

38. Treatment in General
I. Surgery if accessible
II. Radiation if radiosensitive
III. Chemotherapy if chemosensitive
Prognosis depends on type & location

40. Introduction
 15% of primary CNS tumors
 Cranial:Spinal astrocytoma = 10:1
 Cranial: Spinal ependymoma = 3 ~20:1
 Most primary spinal tumors are benign
 Compression symptoms

41. Types of Spinal Tumors
 Extradural: (55%)
 Intradural Extramedullary: (40%)
 Meningioma & neurofibroma
 Intramedullary: (5%)

42. Extradural Spinal Tumors
 Metastatic
 Lymphoma, lung, breast, prostate
 Primary
 Chordoma, neurofibroma, osteoblastoma,
hemangioma
 Meningioma

43. Intradural Extramedullary
Spinal Tumor
 Meningioma
 neurofibroma

50. Intramedullary Spinal Tumor
 Astrocytoma 30%
 Ependymoma 30%
 Other 30%
 Glioblastoma, dermoid, epidermoid, lipoma

51. Clinical Presentation
 Pain
 Weakness
 Paresthesia
 Sphincter disturbance
 Other
 Deformity: scoliosis/ torticollis
 SAH
 Mass

52. Diagnosis
 Plain X-ray
 LP
 Myelogram
 CT
 MRI
 Angiography

53. Differential Diagnosis
 Vascular malformation
 Demyelinating diseases ( MS)
 Transverse myelitis
 Paraneoplastic myelopathy