Central Nervous System Tumors in Children Flashcards by Mario Luna

The etiology of pediatric CNS tumors remains largely unknown. Only 2% to
5% can be ascribed to a known genetic predisposition.

Enumerate the conditions with genetic predisposition to develop CNS tumors in children.

NF1
NF2
nevoid basal cell (Gorlin’s) syndrome

familial adenomatous polyposis

Li Fraumeni syndrome.

How well did you know this?

Not at all

Perfectly

In pediatric CSI, what should be the lower limit of the spine CTV?

The lower limit of the CTV for the spine field should be determined
using MRI.

The lower border of the spinal CTV should include the lower border
of the thecal sac, which can be as high as L5 or as low as S3

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Field matching over cervical spine/risk of over- or underdosage

Angle brain fields

use half-beam block for brain fields

use couch rotation or match line wedge

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Inhomogeneity along spinal axis

Use compensator, MLC

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Irradiation of normal tissues - mandible teeth

Neck extension

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Irradiation of normal tissues - thyroid

Care with level of junction

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Irradiation of normal tissues - heart

Use lower junction

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Irradiation of normal tissues - GI tract

Care with width of spine field

Use protons, IMRT, electrons

How well did you know this?

Not at all

Perfectly

Give a possible solution to improve the outcomes encountered with the following scenarios/problem in CSI:

Irradiation of normal tissues - gonads

Care with lower limit and width of spine field

Use protons, IMRT, electrons

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

LGA’s account to a third to half of all pediatric CNS tumors.

TRUE or FALSE?

True

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Most pediatric CNS tumors are supratentorial.

TRUE or FALSE?

False

Infratentorial

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

What is the most common type of astrocytoma in children?

Pilocytic astroctyoma

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Describe the histology/pathologic picture of pilocytic astrocytoma.

well circumscribed with an associated cystic component.

biphasic pattern with a varying proportion of compacted bipolar cells with Rosenthal fibers and loose-textured multipolar cells with microcysts and granular bodies.

Rare mitoses, occasional hyperchromatic nuclei, microvascular proliferation, and even infiltration of meninges.

KIAA1549-BRAF fusions have been identified in 75% of patients
with PA using an RT-PCR assay from FFPE tissue.

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

What variant of pilocytic astrocytoma, first described in infants and children with
chiasmatic/hypothalamic tumors, appears to be associated with more aggressive
behavior that may include leptomeningeal seeding?

pilomyxoid astrocytoma

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Where are the two most common locations of pilocytic astrocytoma, wherein they account for almost all LGAs in those areas?

cerebellum

anterior optic pathway

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Where are the two most common locations of diffuse astrocytoma?

cerebral hemispheres

pons

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Describe the histology/pathologic picture of diffuse astrocytoma.

well-differentiated fibrillary or gemistocytic neoplastic astrocytes on a background of loosely structured, often microcystic, tumor matrix.

moderately increased cellularity.

nuclear atypia is a diagnostic criterion
(mitotic activity, necrosis, and proliferation are absent)

low Ki-67 and MIB-1 labeling indices.

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

What is the syndrome commonly manifested by young children with chiasmatic/hypothalamic tumors that present with the ff:

emaciation with loss of subcutaneous fat despite normal or increased appetite, alert appearance, increased vigor and euphoria, pallor without anemia, and nystagmoid movements of the eyes

diencephalic syndrome

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Neuroimaging findings in pilocytic astrocytoma

well circumscribed with an associated cystic component.

There is usually little edema or mass effect.
The solid component enhances brightly and uniformly with contrast material.

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

Diffuse or fibrillary astrocytomas are usually not well seen on
nonenhanced CT or MRI and usually show little enhancement with contrast
material.

What sequences usually best demonstrate the extent of disease?

T2-weighted
or
FLAIR

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

For pilocytic astrocytomas and diffuse or fibrillary LGAs, postoperative adjuvant therapy is not indicated after complete resection.

TRUE or FALSE?

TRUE

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

For pilocytic astrocytomas and diffuse or fibrillary LGAs, postoperative adjuvant therapy observation can be an option.

How frequent is surveillance MRI performed?

every 6 months for 3 years.

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

For pilocytic astrocytomas and diffuse or fibrillary LGAs, postoperative adjuvant therapy observation can be an option.

What are the options at the time of progression?

Second surgical resection.

if not resectable RT (or chemotherapy: for children ≤10 and children of all ages with NF1)

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children

What are the indications for RT in LGA?

following incomplete resection in situations when tumor progression would compromise neurologic function (e.g., “threat to vision”)

patients with progressive and/or symptomatic disease that is unresectable.

How well did you know this?

Not at all

Perfectly

Central Nervous System Tumors in Children What is the GTV in LGA?

all disease seen on MRI just prior to RT

Central Nervous System Tumors in Children What is the CTV for fibrillary astrocytoma?

GTV as seen on T2 weighted or FLAIR + 1 to 1.5 cm margins

Central Nervous System Tumors in Children What is the CTV for pilocytic astrocytoma?

GTV as seen on T1-W with contrast + 0 to 1 cm. GTV=CTV is acceptable.

Central Nervous System Tumors in Children What is the standard RT total dose?

50 to 54 Gy Evidence for a dose–response correlation in LGAs in children is scant. Although the European and North American studies that randomized adult patients with LGAs between low dose (45 and 50.4 Gy, respectively) and high dose (59.4 and 64.8 Gy, respectively) radiotherapy failed to demonstrate any advantage for the higher dose, it may be unwise to extrapolate that in children doses of 45 to 50 Gy are as effective as the higher doses of 54 to 55 Gy that until now have constituted standard practice. There are biologic differences between LGAs in children and in adults. As well, children who have progressed on chemotherapy may have tumors that are less sensitive. For now, the recommendation for children with LGAs would be a “standard” dose of 50 to 54 Gy depending on the age of the child and the location of the tumor and its relationship to critical normal structures such as the optic chiasm.

Central Nervous System Tumors in Children Is SRS an option for LGA?

yes. may be considered for pilocytic but not for diffuse. 10 to 20 Gy to the periphery

Central Nervous System Tumors in Children What are the histopathologic features of anaplastic astrocytoma?

nuclear atypia increased cellularity significant proliferative activity.

Central Nervous System Tumors in Children What are the histopathologic features of glioblastoma multiforme?

``` mitotic activity nuclear atypia microvascular proliferation necrosis cellular pleomorphism vascular thrombosis ```

Central Nervous System Tumors in Children Where is the most common locations of HGA in children?

cerebral hemispheres (2/3) remainder equally divided between deep midline structures and cerebellum.

Central Nervous System Tumors in Children What is the standard of care for HGAs?

maximal safe resection + PORT

Central Nervous System Tumors in Children GTV and CTV in HGAs

GTV = tumor plus any T2-weighted MRI abnormality. CTV = GTV + 1.5 cm

Central Nervous System Tumors in Children RT dose (HGA)

59 to 60 Gy | may consider volume reduction to CTV1cm after 50 to 54 Gy

Central Nervous System Tumors in Children Children younger than age 3 with HGAs fare better than older children TRUE or FALSE?

True ``` In contrast to most other tumor types, children younger than age 3 with HGAs fare better than older children, with overall survival at 3 to 5 years in the 33% to 50% range in the North American and United Kingdom Children’s Cancer Study Group/International Paediatric Oncology Society (UKCCSG/SIOP) baby studies. ``` The prognosis may be even better for children younger than age 1.

Central Nervous System Tumors in Children p53 overexpression and a high MIB-1 labeling index appears to be a favorable prognostic factor. TRUE or FALSE?

False p53 overexpression and a high MIB-1 labeling index appear to identify patients with a particularly adverse prognosis

Central Nervous System Tumors in Children What are the three types of optic pathway gliomas?

anterior tumors - confined to optic nerve - optic chiasm +/- nerve posterior tumors -chiasmatic/hypothalamic

Central Nervous System Tumors in Children One third of optic pathway gliomas are associated with what genetic condition, where bilateral involvement of the optic nerves is pathognomonic?

NF-1

Central Nervous System Tumors in Children What is the usual presentation of a patient with optic nerve glioma without NF-1?

proptosis, long-standing

Central Nervous System Tumors in Children MRI findings in optic nerve gliomas?

small, well-circumscribed, with bright enhancement typical for pilocytic astroctyoma.

Central Nervous System Tumors in Children in optic nerve gliomas "and" optic chiasm gliomas, biopsy is necessary to make a diagnosis. TRUE or FALSE?

False.

Central Nervous System Tumors in Children What is the preferred treatment for optic nerve glioma patients predicted to not have functional vision?

surgical resection

Central Nervous System Tumors in Children What is the preferred treatment for optic nerve glioma patients with functional vision for patients with NF-1?

chemotherapy

Central Nervous System Tumors in Children What is the preferred treatment for optic nerve glioma patients with functional vision for infants and patients up to age 5?

chemotherapy

Central Nervous System Tumors in Children What is the preferred treatment for optic nerve glioma patients with functional vision for older patients?

chemotherapy. | RT may be considered.

Central Nervous System Tumors in Children MRI findings in optic chiasm gliomas?

small and well circumscribed and enhance uniformly and brightly with contrast material, suggestive of pilocytic histology

Central Nervous System Tumors in Children What is the appropriate initial step in the management of chiasmatic gliomas in patients with NF-1?

surveillance

Central Nervous System Tumors in Children What is the role of RT in the management of chiasmatic gliomas?

reserved for salvage after chemotherapy definitive treatment of older children without NF-1

Central Nervous System Tumors in Children What is the most common optic pathway glioma?

posterior tumors -chiasmatic/hypothalamic (70%)

Central Nervous System Tumors in Children What is the role of RT in the management of posterior optic pathway gliomas?

progressive disease on chemotherapy for children younger than 10 progressive disease at diagnosis or after surgery for older patients

Central Nervous System Tumors in Children RT dose, posterior optic pathway gliomas younger children ≤5 years

45 to 50 Gy

Central Nervous System Tumors in Children RT dose, posterior optic pathway gliomas older than 5 years

50 to 54 Gy

Central Nervous System Tumors in Children Brainstem Gliomas MRI findings in focal tumors

well circumscribed without evidence of infiltration and edema may be cystic uniform bright enhancement with contrast material, which correlates with pilocytic histology absence of peritumoral hypodensity

Central Nervous System Tumors in Children Brainstem Gliomas Most common location of focal tumors

midbrain and medulla

Central Nervous System Tumors in Children Brainstem Gliomas treatment of choice for focal tumors

surgery

Central Nervous System Tumors in Children Brainstem Gliomas role of RT in focal tumors

same as in other LGAs

Central Nervous System Tumors in Children Brainstem Gliomas Most common location of dorsal exophytic tumors

floor of the fourth ventricle

Central Nervous System Tumors in Children Brainstem Gliomas MRI findings in dorsal exophytic tumors

sharply delineated hypointense on T1W hyperintense on T2 enhance uniformly

Central Nervous System Tumors in Children Brainstem Gliomas treatment of choice for dorsal exophytic tumors

surgery | maximal safe resection

Central Nervous System Tumors in Children Brainstem Gliomas treatment of choice for dorsal exophytic tumors with residual after surgery

observation. routine RT is not indicated.

Central Nervous System Tumors in Children Brainstem Gliomas role of RT in dorsal exophytic tumors

high-grade lesion progressive disease (<9 months postop) inoperable disease

Central Nervous System Tumors in Children Brainstem Gliomas treatment of choice for dorsal exophytic tumors with later recurrence postop

second surgery

Central Nervous System Tumors in Children DIPG DIPG accounts for the majority of brainstem gliomas. TRUE or FALSE?

True 70% to 80%

Central Nervous System Tumors in Children Brainstem Gliomas CT and MR findings in DIPGs

On CT, DIPGs are isodense or hypodense, with little enhancement after contrast injection, similar to diffuse fibrillary astrocytomas at other sites. They are best seen on T2-weighted or FLAIR MRI. The presence of ring enhancement is suggestive of high-grade histology.

Central Nervous System Tumors in Children Brainstem Gliomas Treatment of choice for DIPG?

Central Nervous System Tumors in Children Brainstem Gliomas Conventional RT dose for DIPG?

54/30

Central Nervous System Tumors in Children Brainstem Gliomas GTV and CTV for DIPG?

GTV = T2W or FLAIR abnormality CTV 1-1.5 cm

Central Nervous System Tumors in Children Brainstem Gliomas HFRT dose for DIPG?

39/3/13 | 45/3/15

Central Nervous System Tumors in Children Astrocytoma of the Spinal Cord CTV?

``` solid portion (including intratumoral cysts) margin of 1 to 1.5 cm ``` (at least 1.5 for HGAs)

Central Nervous System Tumors in Children Astrocytoma of the Spinal Cord RT dose

50.4/1.8/28 same for both LGA and HGAs, unlike in adults where HGAs are treated to 54

Central Nervous System Tumors in Children Ependymoma Most common location of myxopapillary ependymoma?

filum terminale

Central Nervous System Tumors in Children Ependymoma Most common presentation of myxopapillary ependymoma?

back pain

Central Nervous System Tumors in Children Ependymoma Leptomeningeal seeding is common despite low-grade histology of myopapillary ependymoma. TRUE or FALSE?

True

Central Nervous System Tumors in Children Ependymoma RT volume (CTV) for PORT in myxopapillary ependymoma

macroscopic residual + cc margin 1.5 cm (or one vertebral body)

Central Nervous System Tumors in Children Ependymoma RT dose for PORT in myxopapillary ependymoma

50.4 Gy

Central Nervous System Tumors in Children Ependymoma Treatment for leptomeningeal seeding (myxopapillary)

CSI curative intent + boost to primary site

Central Nervous System Tumors in Children Ependymoma Most common site for ependymoma (WHO grade II)

ependymal lining of the fourth ventricle

Central Nervous System Tumors in Children Ependymoma Complete resection is more frequently possible in patients with infratentorial ependymomas than in spinal or supratentorial variants. TRUE or FALSE?

False

Central Nervous System Tumors in Children Ependymoma PORT is standard of care in WHO grade II ependymomas. When can you withhold RT?

(a) patients with ependymoma of the spinal cord who have undergone complete resection for whom disease-free survival in contemporary series approaches 100% and (b) selected patients with supratentorial ependymoma, such as those with intraventricular tumors or with extraventricular tumors that are solid and located in noneloquent areas and can be resected with a wider margin.

Central Nervous System Tumors in Children Ependymoma GTV/CTV for WHO grade II ependymoma?

The GTV is a composite of the tumor bed, including any extension caudal to the foramen magnum and taking into account any anatomic shifts because of surgery plus any residual tumor CTV 1 cm (SJCRH) CTV 0.5 (COG)

Central Nervous System Tumors in Children Ependymoma RT dose for WHO grade II ependymoma?

54 to 59.4 | 54 if limited by OARs

Central Nervous System Tumors in Children Ependymoma What is the histology of anaplastic ependymomas?

By definition, an anaplastic ependymoma is a malignant glioma of ependymal differentiation that is characterized by high mitotic activity, often accompanied by microvascular proliferation and pseudopalisading necrosis. There are no histopathologic features that can reliably differentiate anaplastic ependymomas from the more slowly growing and more favorable ependymomas

Central Nervous System Tumors in Children Ependymoma GTV/CTV for anaplastic ependymoma?

tumor bed and any macroscopic residual disease with a margin for the CTV of 1 cm dose similar to WHO grade II CSI was abandoned as standard of care

Central Nervous System Tumors in Children Ependymoma What is a hallmark finging of ependymoma on pathologic specimens?

Rosette formation | from adult CNS chapter

Central Nervous System Tumors in Children Ependymoma boost volume for ependymoma of posterior fossa

(from adult CNS chapter) Historically, for posterior fossa tumors, the entire posterior fossa has been irradiated. However, Paulino has shown that the pattern of failure to be “local,” i.e., within the tumor bed itself. In 9 patients who received RT to the tumor bed + a 2 cm margin, the two failures in this group were within the tumor bed (i.e., there were no failures within the PF outside the tumor bed).

Central Nervous System Tumors in Children Ependymoma In what variant can a neuraxis spread be treated focally rather than CSI?

Myxopapillary

Central Nervous System Tumors in Children Ependymoma When do you include the entire thecal sac in the treatment volume?

when the cauda is involved | taken from spinal chapter

Central Nervous System Tumors in Children Choroid Plexus Tumors What accounts for the majority of CP tumors in children?

Papilloma (CPP) (WHO I)

Central Nervous System Tumors in Children Choroid Plexus Tumors If a CPP tumor has high mitotic activity, what type of tumor is suggested?

atypical (WHO II)

Central Nervous System Tumors in Children Choroid Plexus Tumors Histology of CPP

delicate fibrovascular connective tissue fronds covered by a single layer of uniform cuboidal columnar epithelial cells with round or oval basally situated monomorphic nuclei. low mitotic activity

Central Nervous System Tumors in Children Choroid Plexus Tumors If a CP tumor shows frequent mitosis (>5%/10 HPF), and has increased cellular density, nuclear pleomorphism, blurring of the papillary pattern with poorly structured sheets of tumor cells, and necrotic areas, what is the classification?

carcinoma (CPC) (WHO III)

Central Nervous System Tumors in Children Choroid Plexus Tumors Most common location?

lateral ventricles | causing CSF flow obstruction.

Central Nervous System Tumors in Children Choroid Plexus Tumors neuroimaging findings

usually hyperdense, | contrast-enhancing masses

Central Nervous System Tumors in Children Neuronal and Mixed Neuronal-Glial Tumors What are the two histologies where post-op RT may be indicated?

ganglioglioma and central neurocytoma

Central Nervous System Tumors in Children Neuronal and Mixed Neuronal-Glial Tumors RT dose for typical central neuroctyoma?

50 Gy

Central Nervous System Tumors in Children Neuronal and Mixed Neuronal-Glial Tumors RT dose for atypical central neuroctyoma?

54 Gy

Central Nervous System Tumors in Children Pineocytoma Some will have symptoms of upper mesencephalic tegmental dysfunction consisting of: limitation of upward gaze, lid retraction, retraction nystagmus, and pupils that react more poorly to light than to accommodation. What is this syndrome?

Parinaud syndrome

Central Nervous System Tumors in Children Pineocytoma RT volume (GTV/CTV) and dose?

The target volume is local, consisting of macroscopic residual disease with a margin for the CTV of 1 cm, and the dose, 50 to 55 Gy over 6 weeks.

Central Nervous System Tumors in Children Pineblastoma What is the most common presentation?

enlarging head circumference signs of short duration increased ICP.

Central Nervous System Tumors in Children Pineblastoma Complete surgical resection is difficult. What is the adjuvant treatment?

CSI and chemotherapy

Central Nervous System Tumors in Children What is the second most common type of CNS tumor in the pediatric age group?

Medulloblastoma

Central Nervous System Tumors in Children Desmoplastic MB is associated with a _____ prognosis, particularly in very young children.

good

Central Nervous System Tumors in Children What are the four molecular subgroups of medulloblastoma?

WNT-activated SHH (TP53 mutant/wild tyep) non WNT/non-SHH (3) non WNT/non-SHH (4)

Central Nervous System Tumors in Children Which of the four subgroups of medulloblastoma has the worst prognosis?

group 3

Central Nervous System Tumors in Children Standard-risk MB?

<1.5 cm2 residual on MRI 48-72 hours post op. no evidence of CSF dissemination

Central Nervous System Tumors in Children When to do lumbar puncture for MB?

prior to surgery or at least 2 weeks post-op to avoid artifacts

Central Nervous System Tumors in Children Standard of care for standard-risk MB

CSI 23.4 Gy with a boost to the tumor bed to a total dose of 54.0 Gy, followed by eight cycles of chemotherapy with vincristine, CCNU, and cisplatin.

Central Nervous System Tumors in Children What is the characteristic molecular findings in atypical teratoid rhabdoid tumor

deletion and/or mutation of the INI1 locus on chromosome 22

Central Nervous System Tumors in Children What are the most common locations of CNS germ cell tumors.

Pineal gland | suprasellar region

Central Nervous System Tumors in Children What CNS germ cell tumor is more commonly found in the pineal gland?

NGGCT

Central Nervous System Tumors in Children What CNS germ cell tumor is more commonly found in the suprasellar region?

germinoma

Central Nervous System Tumors in Children Describe the common presentation of pineal germ cell tumors.

*obstruction to csf flow signs of increased ICP hydrocephalus parinaud syndrome

Central Nervous System Tumors in Children Describe the common presentation of suprasellar germ cell tumors.

long history of neuroendocrine deficits later, increased ICP

Central Nervous System Tumors in Children Identify the most likely germ cell tumor involved (with just this data): modest elevation of b-hcg <100 IU/mL)

pure germinomas

Central Nervous System Tumors in Children Identify the most likely germ cell tumor involved (with just this data): extremely elevated b-hcg levels

choriocarcinoma

Central Nervous System Tumors in Children Identify the most likely germ cell tumor involved (with just this data): elevated a-FP

yolk-sac tumor

Central Nervous System Tumors in Children Identify the most likely germ cell tumor involved (with just this data): imaging: heterogeneous with cysts, areas of calcification, and sometimes fat,

teratoma

Central Nervous System Tumors in Children Identify the most likely germ cell tumor involved (with just this data): contains areas of hemorrhage

choriocarcinoma

Central Nervous System Tumors in Children Standard of care for germinomas without leptomeningeal seeding.

whole brain (whole ventricular RT) + margin with concurrent platinum based chemotherapy.

Central Nervous System Tumors in Children RT dose for germinomas without leptomeningeal seeding.

There is less controversy now with regard to the radiotherapy dose and dosefractionation schedule for germinoma. Results are excellent with a CSI dose as low as 21 Gy even in patients with leptomeningeal spread. The total dose to the primary site has typically been 40 to 45 Gy but probably can be safely reduced to 30 Gy or even to 24 Gy in patients treated with a combined chemotherapy–radiotherapy regimen who have had a complete response to chemotherapy. Finally, because germinoma is a very radiosensitive tumor, a fraction size of 1.5 Gy can be used, which, in theory, further reduces the risk of injury to normal structures.

Central Nervous System Tumors in Children RT dose for NGGCT.

The usual dose to the whole ventricle volume or CSI is 30 to 36 Gy and to the primary site, 54 Gy. Patients who have less than a complete response to chemotherapy fare poorly.

(from in-service bank) 1. Considered WHO 1 brain tumors except a. pilocytic astrocytoma b. subependymoma c. myxopapillary ependymoma d. classic ependymoma

(from in-service bank) 2. Are non-germinomatous germ cell tumors, except a. choriocarcinoma b. endodermal sinus tumor c. embryonal carcinoma d. hemangiopericytoma

(from in-service bank) 3. These age group will have the worst neurocognitive toxicity in children who undergo radiation therapy to the CNS a. <3 b. 4-7 c. 7-10 d. >10

(from in-service bank) 4. Post-op MRI if the brain is best done in the ff a. 1-2 weeks post-op b. within 48 Hours post-op c. anytime d. 6 mos post-op

(from in-service bank) 5. True or False: Glioblastoma multiforme is more common than anaplastic astrocytoma in children.

False

(from in-service bank) 6. These tumors usually have poorly defined margins with central necrosis and vasogenic edema a. Low grade astrocytoma b. Diffuse Intrinsic Pontine Glioma c. High Grade Astrocytoma d. Craniopharyngioma

(from in-service bank) 7. Which marker is always elevated in NGGCT ___ “but never in pure germinoma”

aFP

(from in-service bank) 8. One criteria for HIGH Risk Medulloblastoma is the size of residual disease after surgery and that is > _____ cm2.

1.5

(from in-service bank) 9. Best describes the prognosis of Low grade gliomas EXCEPT a. OS in the 80-90% b. Adjuvant RT is necessary for all even after GTR. c. With RT, 5 yr OS is 67-100% d. GTR is the primary Tx,

(from in-service bank) 10. True about craniopharyngiomas EXCEPT a. Best treated with 54Gy to tumor b. Usually associated with solid and cystic components c. PFS of gross total resection and limited resection plus RT are the same. d. Chemotherapy is generally given post-RT.

(from in-service bank) 11. CCG (Childrens Cancer Group) introduced these protocols in the treatment of medulloblastoma. EXCEPT a. 23.4 Gy CSI with chemo with 54Gy PF boost in standard risk MB b. Use of vincristine, CCNU, prednisone as chemotherapy agents c. Chemotherapy provides survival benefit for T3-T4/M1-3 disease d. None of the above

(from in-service bank) 12. Typical target volume for this tumor is the ff: CTV1: GTC/edema + 2cm (on T2), CTV2 GTV+1 cm (on T1) a. Low grade astrocytoma b. NGGCT c. Medulloblastoma d. High grade astrocytoma