Ch 32 - CNS Cancer Flashcards
The spinal cord is the continuation of the ________.
Medulla oblongata
Anterior and lateral portion of the spinal cord contains _______ and _____
Motor neurons and tracts
The posterior portion of the spinal cord contains _______
Sensory tracts
Blood supply of the brain comes from ________ and ________ via the Circle of Willis
From the internal carotid arteries and vertebral arteries
Gray matter is composed of
Supportive nerve cell bodies
White matter is composed of bundles of
myleinated nerve fibers,
Axons carries impulses _______ from the cell body
Away
Dendrites carries impulses _______ the cell body
Towards
Spinal cord extends to what vertebral body
Spinal cord extends to L1/L2
Spinal canal consist of
CSF- cerebral spinal fluid
The blood Brain barrier protect the brain from
Potentially harmful substances and hinders the penetration of some substances into the brain and CSF
BBB limited our treatment because
There’s small spaces where molecules in the blood cannot get into the different channels in the brain tissues
In order for substances to pass through the BBB they must be _____
Lipid soluble which includes alcohol, nicotine, and heroin
Water soluble substances needs _______ to cross the BBB via ______
Carrier molecule via active transport
Most CNS tumors are what kind
Metastatic tumors
The treatment of choice for PRIMARY brain tumor is
Surgery
Metastatic tumors to the brain usually originate in the
Lungs
What is not consider as the 3 important prognostic indicators for CNS tumors
The size
What are the 3 important prognostic indicators for CNS tumors
Type and grade of tumor
Age
Karnofsky score
T/F
Primary CNS tumors occur more often in the spine than in the brain
False
Brain tumors typically spread by the way of
Direct extension
Why would a benign tumor be considered malignant
Due to its location and its close proximity to other structures
SRS is indicated for metastatic lesions that is larger than
3cm
What is the TD5/5 for partial brain irradiation
6000cGy (60Gy)
What is the TD5/5 for whole brain
5000cGy (50Gy)
What is the TD5/5 for spinal
4500-5000 (45-50Gy)
What is the most common malignant CNS pediatric tumor
Medulloblastoma
Which part of the brain is the center for memory, learning, reasoning, judgement, intelligence and emotions
Cerebrum
SRS is thought to be accurate within
1mm
At what dose can hair lose become permanent
Greater than 4000 (40Gy)
At what dose is hair loss temporary
Between 2000-4000cGy (20-40Gy)
What would you recommend a patient wash their hair with while on treatment for a brain tumor
A mild shampoo (baby shampoo)
How much CSF circulates within the CNS
3-5 ounces
Only these types can pass through the BBB
Lipid soluble
Brain tumors occur most often in people ages
Pediatric (3-12yrs)
Geriatrics ( 50-80yrs)
What is the term for the structure in the brain that is Latin for little brain”
Cerebellum
Patients that are unable to work fall nto what range of the karnofsky scale
40-70
What is the TD5/5 for the lens of the eyes
10Gy
What is the TD5/5 for the optic chiasm
50Gy
Which of the following does NOT provide protection for the brain
Cerebellum
A gliomas spreads primarily by the way of …
Local invasion (direct extension)
The BBB protects…
The brain from potentially toxic substances
But not heroine or alcohol
Weakened proximal pelvic muscle, impotence, and bladder paralysis might indicate a signal tumor in what region
Limbo sacral
What is the current 5 yr survival of patients with PRIMARY CNS tumor
35%
What type of tumor is classified by primitive neuroectodermal cell
Medulloblastoma
What is the most common type of brain tumor
Metastatic lesions
Where do most brain mets originate from
Lungs
Which cell is responsible for myelin production
Schwann cells
What factors can limit the usefulness of surgery for CNS neoplasm
Tumor location an extent
Patient status
Risk of neurological damage
Which portion of the brain is the site for intelligence and judgement
Cerebrum
What condition is a contradiction for SRS
5 lesions
What is one of the late effects of brain radiation in children
Decreased IQ
Which of the following is the most significant to the prognosis of brain tumors
Tumor grade
Which of the following Beam arrangements is most typical for treatment of a malignant malignant primary brain tumors
Small field with 1-3cm margins
What is the dose at which radiation necrosis of brain tissue is most likely to occur
6000cGy (60Gy)
Epilation may be permanent when the cranial is treated beyond the threshold dose of ____ cGy
Beyond 4000cGy
Patients treated to the cranial should be advised to protect their heads from direct sunlight because the sun
Enhances radiation induced side effects
These are small round blue cells that become CNS malignancies
Primitive neuroectodermal cells
Medullolastoma mostly Present in the
Cerebellum
What’s the 3 yr survival rate for GBM is roughly
2%
How much cerebral spinal fluid (CSF) is secreted each day
Half liter (0.5L)
A fold of tissue that separates the brain hemisphere and the cerebrum from the cerebellum is the ….
Tentorium
Brain tumors are the ____ leading cause of death in children
Second and is the most common pediatric solid tumor
Function of this portion of the brain is coordination of voluntary muscular movement and is known as the little brain
Cerebellum
75% of all CNS tumors occur in the
Cerebrum
Gliomas of pediatrics occur in the
Cerebellum
Of the 3 prognostic indicator, __________ is the primary prognostic indicator for CNS tumors
Tumor grade associated with tumor type
The brain is protected by
Cranial bones
Meninges
CSF
For the brain:
____ matter is located on the outside, forms the cortex and have supportive nerve cells.
_____ after is on the inside and contains bundles of myelinated fibers that sends and receives signals
Gray Outside
White Inside
For the spinal cord:
___ matter is on the outside while ____ matter is on the inside
White Outside
Gray Insides
The spinal cord extends to what level
L1-L2
What is aphasia
Difficulty speaking
What is hemiplegia
Paralysis on one side of the body
What is paresis
Weakening of the muscles
Symptoms for frontal tumor
Personality changes
Memory loss
Gait disorder
Speech changes
Symptom for parietal tumors
Loss of vision
Spatial disorientation
Seizures
Symptoms for occipital tumors
Loss of sight
Symptoms for temporal tumors
Hearing and smelling changes
Hallucinations
The _____ area is the most frequent site for spinal tumor seeding
Lumbosacral
Presentation for spinal cord tumor
Pain
Weakness
Loss of sensation
Weakness in distal part of extremity
When _____ is present, whole brain treatment is given
Metastatic disease
Most common site in the brain for brain mets
Cortex
Whole brain technique is used to treat
Brain mets
Lymphoma
What is the typical dose to treat whole brain
20-40Gy
The Treated Volume (TV) is the volume enclosed by the desired prescription isodose and contains…
GTV, CTV, PTV
The Irradiated volume (IR) is the tissue volume that receive significant dose and contains…
GTV, CTV, PTV and TV
The CTV is ______ cm beyond the GTV
1-3cm beyond the GTV
The PTV is ____cm beyond the CTV
0.5cm-1cm beyond the CTV
TD5/5 for spinal cord
47Gy
TD5/5 for ear
30-55Gy
Td5/5 for brain stem
50Gy
SRS are done on tumors that are
Spherical
LESS than 5cm
Accuracy occurs to 1mm
