4._CNS_Tumors
Download
Report
Transcript 4._CNS_Tumors
Dr. Zana A. Mohammed
M.B.Ch.B., F.I.B.M.S. Neurology
Faculty of medical science
School of medicine
University of Sulaimaniah
Brain compartments
Brain tumor
A brain tumor is a localized intracranial lesion which
occupies space within the skull.
• Incidence of primary brain tumors
(benign or malignant) 12.8/100,000
• 10%–15% of cancer patients develop brain
metastases
• Often unknown
• Risk factors:
o
o
o
o
o
o
o
Genetic changes
Family history
Errors in fetal development
Ionizing radiation
Environmental hazards (including diet)
Viruses
Injury or immunosuppression
• Primary ( benign and malignant).
• secondary (metastatic)
o 35% - lung
o 20% - breast
o 10% - kidney
o 5% - gastrointestinal
tract
• Location ( intra-axial and extra-axial)
Clinical features
There are three groups of symptoms and signs resulting from
brain tumors:
• Raised intracranial pressure
• Epilepsy
• Evolving focal neurological deficit.
Raised intracranial pressure
The cardinal features of raised intracranial pressure are:
• Headache
• Vomiting
• Papilledema
• False localizing signs
• Depression of conscious level
• Signs of tentorial herniation and coning.
• Headaches of raised intracranial pressure tend not to be
extremely severe, they are usually generalized throughout the
head, and they tend to be worse in the mornings when the patient
wakes. They sometimes wake the patient earlier than his normal
waking time.
• papilledema: The patient may report transient blurring or
loss of vision. Such visual obscurations should stimulate urgent
investigation and treatment.
False localizing signs
We have seen that a mass lesion in one compartment of the brain
can induce shift and compression in parts of the brain remote
from the primary lesion producing false localizing signs.
• The descent of the brainstem may stretch the 6th cranial nerve
to produce a non-localizing lateral rectus palsy:
• The ventricular dilatation above midline CSF obstructive
lesions, or above posterior fossa lesions may produce:
—intellectual and behavioral changes suggestive of primary
frontal pathology;
—an interference with vertical eye movements (upper midbrain)
because of the dilatation of the posterior part of the 3rd ventricle
and aqueduct
Epilepsy
• Focal epilepsy, focal epilepsy progressing on to a generalized
tonic–clonic seizure, tonic–clonic seizures with post-ictal
focal neurological signs, and tonic–clonic epilepsy without
any apparent focal features may all indicate the presence of a
tumor in the cerebrum.
• Epilepsy is not a feature of posterior fossa tumors.
• Epilepsy is not commonly caused by tumors, and less than
50% of cerebral tumors produce epilepsy, but the occurrence
of epilepsy in adult life should prompt the possibility of a
brain tumor in the doctor’s mind.
Focal neurological deficit
• The presence of a tumor impairs the function of the part of
the brain in which it resides. The nature of the evolving focal
neurological deficit clearly depends on the site of the lesion.
• Tumors near the midline and in the posterior fossa may
produce marked features of raised intracranial pressure
before there are many localizing signs.
• Gliomas
o
o
o
•
•
•
•
Astrocytoma (Grades I & II)
Anaplastic Astrocytoma
Glioblastoma Multiforme
Oligodendroglioma
Ependymomas
Medulloblastoma
CNS Lymphoma
Gliomas are seen to appear in both the
benign and malignant groups of tumors.
• Astrocytomas are by far the most
common glial tumor; derived from
oligodendrocytes, ependyma, neurons,
primitive neuroectodermal or other
tissues are much rarer.
• Gliomas are classified histologically
from grade 1 (benign) to grade 4
• (the highly malignant glioblastoma
multiforme).
• Benign gliomas are, unfortunately,
much less common than malignant
ones and have a tendency to become
more malignant with time.
• Grade I
• Non-infiltrating
•
•
•
Grade II
Infiltrating
Slow growing
• Grade III
• Infiltrating
• Aggressive
•
•
•
•
Grade IV
Highly infiltrative
Rapidly growing
Areas of necrosis
•
•
Grades II-IV
Mixed astro/glio
•
•
•
•
Slow growing
Benign
HCP/ICP
Surgery, RT, Chemo
•
Small cell embryonal
neoplasms
• Malignant
• HCP/ICP
•
•
•
•
Primary CNS lymphoma
B lymphocytes
Increased ICP
Brain destruction
•
•
•
•
•
Meningioma
Metastatic
Acoustic neuromas (Schwannoma)
Pituitary adenoma
Neurofibroma
Meningioma
• Nearly always benign.
• They may arise from any part of the
meninges, over the surface of the
brain, from the falx, or from the
tentorium.
• There is a plane of cleavage
between tumor and brain tissue
which makes total removal a
definite possibility.
•
•
•
•
Usually benign
Slow growing
Well circumscribed
Easily excisable
• Benign
tumors
of
the
Schwann cells
• Located in CP angle and the
internal auditory meatus in the
petrous temporal bone.
• produce progressive unilateral
nerve deafness, associated 5th
and 7th nerve dysfunction,
unilateral cerebellar signs and
evidence of raised intracranial
pressure.
• Early diagnosis is critical
•
•
•
•
•
Benign
Anterior pituitary
Endocrine dysfunction
chiasmatic compression
Bitemporal hemianopia
Pituitary adenomas
1. Space-occupying effects:
• suprasellar extension to compress optic nerves/chiasm/tracts.
Bitemporal hemianopia resulting from chiasmal compression. so
monocular blindness due to optic nerve compression and
homonymous hemianopia from optic tract compression according
to location of pituitary gland.
• Lateral expansion may compress structures on the lateral wall of
the cavernous sinus (cranial nerves, 3, 4, 5a and 6), producing
double vision and forehead numbness.
• Forward and downward expansion of the adenoma results in
enormous expansion of the pituitary fossa and occasional erosion
through bone into the sphenoidal air sinus.
2. The endocrine disturbances that accompany the development
of a pituitary adenoma are:
• Positive if the tumor cells are secretory (prolactin, growth
hormone, etc.)
• Negative if the tumor is preventing normal secretion by the
rest of the pituitary gland (varying degrees of pan
hypopituitarism).
• Cystic tumor coming from remnant of
Rathke’s pouch
• Hypothalamic-pituitary axis dysfunction
•
•
Peritumoral edema
Necrotic center
• 80% of metastases occur supratentorially and 20%
infratentorially (distribution of cerebral blood supply)
• Up to 75% of patients have neuroimaging evidence of
multiple metastases at presentation
• Lung cancer and melanoma are most likely to produce
multiple metastases
• Renal cell carcinoma, breast cancer, and colon cancer are
most likely to produce single brain metastasis
• Retroperitoneal, pelvic, gastrointestinal primary tumors
have predilection for posterior fossa
• Metastasis occurs with hematogenous
spread and typically land at gray matter
white matter junction because of abrupt
change in blood vessel caliber.
• Except for certain neoplasms such as
malignant melanomas that can penetrate
arterial (arteriolar) walls and are often
hemorrhagic, most tumors usually
penetrate capillary beds to arrive at their
destination
• Radiological Imaging
o
o
o
o
o
Computed Tomography scan (CT scan) with/without
contrast
Magnetic Resonance Imaging (MRI) with/without
contrast
Plain films
Myelography
Positron Emission Tomography scan (PET scan)
• LP/CSF analysis
• Pathology
•
•
•
•
•
Resection
Craniotomy
Stereotaxis Surgery
Biopsy
Transsphenoidal
• Drug therapy – Palliative
o
Done for symptom treatment and to prevent
complications
NSAIDs
Analgesics
Steroids (Decadron, medrols, prednisone)
Anti-seizure medications (phenytoin)
Histamine blockers
Anti-emetics
Muscle relaxers (for spasms)
Mannitol for ICP –New Hypertonic saline
•
•
•
•
•
•
•
•
Increased ICP
Hematoma
Hypovolemic shock
Hydrocephalus
Atelectasis
Pulmonary edema
Meningitis
Fluid and electrolyte
imbalances (ADH)
•
•
•
•
Wound infection
Seizures
CSF leak
Edema
• Damages DNA of rapidly dividing cells
• 4000–6000 Gy total dose
• Duration of 4–8 weeks
• Slows cell growth
• Cytotoxic drugs
o
CCNU, BCNU, PCV, Cisplatin, Etoposide,
Vincristine, Temozolomide (Temodar)
A patient is being directly admitted to the
medical-surgical unit for evaluation of a brain
mass seen in the frontal lobe on a diagnostic CT
scan. Which of the following signs and
symptoms would the patient most likely
present with?
Personality changes
b. Visual field cuts
c. Difficulty hearing
d. Difficulty swallowing
a.
Case 1
A 65-year-old widow presents with a 6-month history of
unsteadiness. She has started to veer to the left. She has
been well prior to this, apart from a longstanding hearing
problem and surgery for colon cancer 5 years ago. On
examination she has an ataxic gait, slight leftwards
nystagmus, an absent left corneal reflex and marked leftsided deafness. There is no papilledema.
a. What do you think is the cause of her symptoms?
Case 2
A 45-year-old oil company executive returns from secondment in
Nigeria because of ill health. Over the last 3 months he has
become slow and erratic, making frequent mistakes at work and
getting lost on his way home. His memory has become poor and
he has had difficulty in finding his words. His appetite has faded
and he has lost weight. In the last 2 weeks he has become
unsteady on his feet and incontinent of urine.
On examination he is thin. He has no fever but his axillary and
inguinal lymph nodes are slightly enlarged. He is drowsy. He had
bilateral papilledema. He has difficulty cooperating with a
neurological examination and becomes increasingly irritated when
you persist.
a. What do you think is the cause of his symptoms?
Thanks