CH 14--Nervous System 4/Tumors

Question 1

Neoplasms of the CNS

• Include those originating within the brain, spinal
cord, or meninges
• Include also metastatic tumors originating in other
sites
• Benign lesions may result in death due to
compression of vital structures
• Primary mailgnant tumors of the brain rarely
disseminate to other parts of the body

Answer 1

KNOW BASICS

Question 2

Intracranial Tumors

1–* Incidence: relatively RARE
2–* Origin: _____ cells (60%) & meninges (20%)
3–* Site: supratentorial: more in adults (70%) infratentorial: more in children (70%)
4–* Spread:
- direct infiltration & destruction of brain tissue
- within cranial cavity by CSF

7 Types:
Astrocytoma, Oligodendroglioma, Ependymoma
Medulloblastoma, Meningioma, Schwannoma and
Neurofibroma

Pathology & clinical features:

1. Compression & irritation of adjacent tissue
2. Infiltration & destruction of adjacent tissue
3. Cerebral edema due to formation of new B.Vs.
4. Increased ICP
5. Hydrocephalus

Answer 2

glial

Question 3

Intracranial Tumors 7 TYPES

1. _____________ (Glioma)
   - MOST frequent type of brain tumors
   - 2 types: cerebellar and cerebral
   A—–Cerebellar:
   * Age: children & young adults (7-9 years)
   * Site: vermis & cerebellar hemisphere
   * Very slowly growing, best prognosis
   * Degeneration & cyst formation mural nodule
   B— Cerebral:
   * Site: white matter of cerebral hemisphere in adults
   * 3 different types:
2. Well differentiated (grade I)
3. Anaplastic (grade II)
4. GLIOBLASTOMA multiform (grade III)
   - Most common type of astrocytoma
   - Age: 40-70 years
   - Arises from frontal lobes, crosses corpus callosum to other side (_________________ shape)

Answer 3

Astrocytoma

Butterfly

Question 4

Intracranial Tumors 7 TYPES

2. Oligodendroglioma

• Age: adults (30-50 years)
• Site: oligodendroglia in_________ matter of cerebral
  hemisphere
• SLOWLY growing, gelatinous (secretion of
  mucopolysaccharide)
• Either:
  i. pure form
  ii. mixed with astrocyte that grows faster

Answer 4

white

Question 5

Intracranial Tumors 7 TYPES

3. Ependymoma

• Origin: ependymal cells lining ventricles and central canal
• Age: more common in _______
• Site: floor of 4th ventricle, grows slowly&raquo_space;>obstruction&raquo_space;>hydrocephalus
• Spread via ______
• Relatively good prognosis

Answer 5

children

CSF

Question 6

Intracranial Tumors 7 TYPES

4. Medulloblastoma

• Origin: primitive neuroectodermal cells
• Age: most common intracranial tumor of ________
• Site: _________ (vermis)
• Complications:
  1. cerebellar signs (e.g. loss of motor coordination)
  2. obstructive hydrocephalus
  3. spread via CSF
• With multimodality therapy, including radiation &
  chemotherapy, 75% of patients survive 5 years or more

Answer 6

children

cerebellum

Question 7

Intracranial Tumors 7 TYPES

5. Meningioma

• Most _______ and resectable tumors of the nervous system
• Origin: meningothelial cells of arachnoid
• Age: 40-50 years with female predominance
• Site: occurs along venous sinuses
  It Grows slowly = irregular firm mass = compresses brain

Answer 7

benign

Question 8

Intracranial Tumors 7 TYPES

6. Schwannoma—-The cut surface of a schwannoma is similar to that of many mesenchymal neoplasms, with a “fish flesh” soft tan appearance.

• is a BENIGN tumor
• Origin: Schwann’s cells (produce collagen & myelin)
• Site: along the course of 8th cranial nerve at
  cerebellopontine angle (acoustic neuroma)
• Encapsulated mass attached at periphery of nerve
  compressing it
• Nerve fibers are sprayed OUT on one side of mass
  (not within) → permits _______ ________ without
  sacrificing nerve

Answer 8

surgical removal

Question 9

Intracranial Tumors 7 TYPES

7. Neurofibroma

• Origin: Schwann cells & fibroblasts
• Non-capsulated fusiform expansion of nerve
• Nerve fibers are scattered ______tumor (mass can NOT be removed surgically without sacrificing the
  nerve)

Answer 9

within

Question 10

_______ _____________________ disease (NF1)
Several larger (>1.0 cm) café-au-lait macules on the
UPPER chest and multiple small macules in the axillae
(axillary “freckling”) in a brown-skinned female

Answer 10

von Recklinghausen’s

Question 11

Metastatic Neoplasms

• The______ is a common site for metastatic lesions
• These occur predominantly in the ______ (why?)
• May involve the meninges as well as brain parenchyma
• Most common PRIMARY SITES = Lung, breast, and malignant melanomas
• ________ abnormalities may be the first clue to the
presence of a visceral carcinoma (particularly the LUNG!)

Answer 11

brain

elderly

Neurologic