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87 Cards in this Set
- Front
- Back
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What is defined as a brain tumor?
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A tumor in regions of brain, malignant or benign, based upon microscopic appearance of mass
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Where do 50-25% of astrocytomas occur?
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Cerebellum - majority low-grade histology
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According to the WHO classification system for astrocytomas, what is classified at Grade I?
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Pliocytic or subependymal giant-cell astrocytoma
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What is classified as Grade II?
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Pilomyxoid, diffuse, or polymorphic astrocytoma
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What is classified as Grade III astrocytoma?
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Anaplastic astrocytomas
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What is classified as Grade IV astrocytoma?
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Glioblastoma muliforme
Giant-cell glioblastoma or gliosarcoma |
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How do Grade III and IV differ from Grade I or II?
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Higher mitotic activity
Grade IV = vascular changes & necrosis |
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T or F: The majority of Astrocytomas that develop in the brain stem are benign.
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False - majority malignant histology
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What percentage of astrocytomas occur in the optic pathway?
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5% - most low-grade histology
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T or F: 7% of astrocytoma occur in the cerebral hemispheres
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False - 7% in hypothalamus (low grade)
25% in cerebral hemispheres (equal low-grade & malignant) |
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What type of brain tumor has a rapid onset of symptoms?
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Brainstem Glioma (anaplastic astrocytoma or glioblastoma of brainstem)
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Are the majority of brainstem glioma's operable?
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No - less than 10% will survive longer than 18mo from time of diagnosis
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What is the most common malignant primary CNS tumor?
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Medulloblastoma - accounts 20% of all Pedi brain tumors
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What cell histology is typically associated with Medulloblastoma?
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Highly cellular, small, round, blue-cell tumor
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Where does Medulloblastoma typically arise from in the brain?
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Cerebellum
or 4th Ventricle |
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Does Medulloblastoma grow fast or slow?
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Fast - aggressively metastasizes through CNS & extraneurally into BM & viscera
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In what type of brain tumor does 2/3 of the cases occur as infratentorial lesions, often in the posterior fossa?
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Ependymoma - 9% of all Pedi brain tumors
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What are examples of a Grade I ependymoma?
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Grade I = Subependymomas (benign, slow growing)
Myxopapillary ependymomas (variant w/favorable prognosis) |
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What is a Grade II ependymoma?
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Grade II = Classical ependymoma
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What classifies a Grade III ependymoma?
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anaplastic, although may develop through malignant progression from low-grade
- typically anaplastic on initial biopsy |
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What percentage of Pedi brain tumors do Craniopharyngioma's account for?
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6-9%
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Where do Craniopharyngioma arise from in the brain?
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The sella (adjacent to pituitary gland, the hypothalamus, & optic nerve
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What is considered the second most common neoplasm & most common solid tumor in children?
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Tumors of the CNS
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What percentage of CNS tumors are located in the posterior fossa (infratentorial region)?
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60% - eg., cerebellar astrocytomas, medulloblastomas, ependymomas
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What percentage of CNS tumors are located in the supratentorial region?
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40% - eg., astrocytomas, hypothalamic, & optic pathway tumors, craniopharyngiomas
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What are some possible chromosomal sites of oncogenesis in brain tumors?
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- Chromosome 17 in Medulloblastoma & astrocytoma
- Chromosome 10 in glioblastoma |
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What is diagnosis often difficult to establish?
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Symptoms mimic common childhood illnesses & vary depending on location & growth rate of tumor
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T or F: Posterior Fossa symptoms are commonly associated with increased ICP
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True - (eg., HA, vomiting, ataxia, nystagmus, diplopia)
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What are cranial nerve deficits typically indicative of?
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Brainstem involvement - from tumor, infiltration, & compression of surrounding structures(hydrocephalus)
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What are symptoms of supratentorial involvement?
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Hemiparesis
Seizures Visual changes Intellectual problems |
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How do midline tumors in the hypothalamus/pituitary region present?
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- Visual changes
- Endocrine abnormalities - Increased ICP |
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What consists of the "classic triad" of symptoms from increased ICP?
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1. morning headaches
2. lethargy 3. n/v |
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What are the more common initial signs of increasing ICP?
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Subacute - declining academic performance; personality changes, fatigue, & vague intermittent HA.
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What are some signs of increased ICP in younger children?
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- Increased irritability
- Increased Head Circ - Bulging fontanel (s) - "sun setting" sign |
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What is the "sun setting" sign?
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LImited upward gaze &
Forced downward deviation of eyes |
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What are VP shunts used for?
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Post surgical & to treat persistent hydrocephalus not resolved after tumor resection or biopsy
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What surgical procedure could eliminate the need for a permanent VP shunt?
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Endoscopic Anterior Third Ventriculostomy (creating an opening in floor of 3rd ventricle to establish CSF pathways)
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What is the gold standard test when diagnosing a brain tumor?
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MRI of the brain
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What imaging is needed if there is an infratentorial tumor?
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MRI of the spine
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Why would one need an MRA (Magnetic Resonance Angiography)?
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If there is concern about the vascularity of the tumor
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What would a PET scan be used to evaluate?
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The metabolic activity of the tumor
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What diagnosis requires a BMA and biopsy?
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Medulloblastoma
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Why should we consider the tumor's rate of cell growth?
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High-grade tumors have a poorer prognosis
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What has improved survival for patient's w/brain tumors?
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Surgical accessibility
- 95% w/low-grade tumors are cured - w/high-grade tumors when 95% of tumor is removed |
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T or F: Infants with malignant tumors have a favorable prognosis
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False - infants have a poor prognosis
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What is the primary treatment for brain tumors?
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Surgical resection
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What advances have improved surgical outcomes?
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Techniques with MRI and stereotactic, or MRI computer-guided surgery - minimizes injury to healthy brain tissue
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What is one of the risks associated with post-surgical complications?
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Posterior Fossa Syndrome
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Mutism, speech disturbances, dysphagia, decreased motor function, cranial nerve palsies & emotional lability are symptoms of what?
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Posterior Fossa Syndrome
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How quickly can s/s of Posterior Fossa Syndrome present?
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24-100+ hours after surgery
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T or F: Radiation is the oldest treatment for brain tumors
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True
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What is radiation treatment used for in the treatment of brain tumors?
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Treat Malignant tumors or deep benign lesions w/large amount of residual disease
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How does radiation get rid of a brain tumor?
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It targets the tumor cells DNA and affects the ability of cells to continue dividing
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What has improved accuracy of radiation treatment and therefore minimal damage to healthy tissue?
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3D imaging using CT & MRI, and focused irradiation
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What age group is radiation therapy delayed in?
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Younger than 3yrs - detrimental to a developing brain
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What does standard radiation therapy typically consist of in terms of dose?
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200 cGy per treatment daily;
- total dose 5,500 - 6,000 cGy to local field |
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What is a typical spinal dose of radiation?
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Usually 2,400 cGy
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What type of radiation can be used for brain tumors that result in lower morbidity but higher total dose given?
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Hyperfractionated radiation treatment = 100 cGy BID (at least 6 hrs apart); total dose 7,200 cGy
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T or F: Chemo is a standard treatment for only some brain tumors
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True - with or as an adjuvant to radiation therapy
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List the chemo most commonly used to treat Pedi brain tumors
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1. Vincristine (Oncovin)
2. Carmustine (BCNU) 3. Lomustine (CCNU) 4. Carboplatin (CBDCA) 5. Cisplatin (Platinol) 6. Etoposide (VP16) 7. Cyclosphosphamide (Cytoxan) 8. Thiotepa (Thiotepa) 9. Temozolomide (Temodar) 10. Irinotecan (CPT-11) |
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What patient population & diagnosis receive HD chemo & Auto SCR in stead of radiotherapy?
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Patient's younger than 3 yrs w/highly malignant tumor & minimal residual disease
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What benefit can monoclonal antibodies provide in treating a brain tumor?
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Inhibit angiogenesis - preventing formation of blood vessels from surrounding tissues to form = limits nutritional supply of tumor
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What are monoclonal antibodies?
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Immunoglobulins produced in a lab that bind to specific target on a cancer cell = antitumor effect
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What are 2 key aspects of supportive care of a brain tumor patient?
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- Minimize risk for increased ICP
- Maintain hydration/euvolemia [use Mannitol & lasix for diuresis] |
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What is treatment goal for "low grade astrocytomas"?
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Gross total resection = greater than 95% removal
- GTR = cured |
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T or F: Low grade astrocytomas of cerebellum recurrence is very low
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True
- MRI monitors progress |
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What treatment option has best prognosis for "low-grade astrocytoma (supratentorial)"?
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GTR if possible - usu. if frontal, parietal, or temporal tumor
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When is chemotherapy or local field radiation is used to treat low-grade astrocytoma (supratentorial)?
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midline tumors that are not completely resected
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What type of brain tumor accounts for less than 20% of all brainstem tumors and is often in the medulla?
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Low-grade (exophytic) astrocytomas of brainstem
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What is a significant post Op risk after de-bulking a low-grade exophytic astrocytoma?
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Lower cranial nerve problems - can affect swallowing and breathing
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What treatment for exophytic astrocytomas have been used for older children with good results?
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Local field radiation therapy
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What tumor has a rapid onset of symptoms, diffuse appearance on MRI, and usu. involves multiple levels of brainstem?
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High-grade astrocytomas of the brainstem
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T or F: Morbidity from surgery outweighs its advantages when considering treatment for a high-grade astrocytoma of the brainstem
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True - treatment is usu. radiation w/ or w/out chemo or biological therapy
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What is the median survival time after a patient has been diagnosed with a high-grade astrocytoma of the brainstem?
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less than 18months to live
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What is the common presenting symptom of medullablastoma?
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morning headaches w/forceful or projectile vomiting (incr'd ICP)
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What can occur secondary to mass effect and obstruction of the CSF flow from the 4th ventricle?
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Hydrocephalus
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What is treatment offers the best prognosis for a pt. w/Medulloblastoma?
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Gross total resection (GTR) w/out metastatic disease at diagnosis
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What treatment would be used in a child 2yrs old w/diagnosis of medulloblastoma?
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HD chemo w/Auto SCR
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What percentage of ependymoma tumors are found in the posterior fossa (4th ventricle)? supratentorial?
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60-75% = posterior fossa
25-40% = supratentorial |
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Is GTR difficult or easy w/ependymoma tumors?
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Difficult - b/c 4th ventricle is so close to the brainstem
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What is the most siginificant prognostic indicator for ependymoma tumors?
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Extent of surgical resection
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Why is GTR challenging with a craniopharyrngioma tumor?
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B/c so close to hypothalamus, pituitary gland, and optic chasm
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T or F: Surgery morbidity and mortality are significant for craniopharyngioma tumors
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True
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What is the treatment for residual craniopharyngioma tumor post resection?
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Focal radiation therapy
Intracystic radioactive implants Chemotherapy |
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What patients will more commonly have recurrence of their brain tumor?
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- infants
- malignant astrocytomas - subtotally resected low-grade tumors |
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What brain tumor is most frequently associated with late relapse?
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Medulloblastoma
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Is HD chemo with SCR considered for patients with recurrent malignant tumors & minimal residual disease?
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Yes
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