Pediatric HGG Flashcards
What percent of pediatric tumors are HGG
12%
What percentage will disseminate
Around 25-50% will disseminate
What is the median survival
1-2 years
Infants usually do better
What is the workup
H&P
Neurological exam
MRI
Biopsy from tumor whenever possible
Max safe resection
Post op MRI
Which group has H3 and H3.1 mutations and what do these mutations cause
Only in kids
These mutations lead to global hypomethylation
What % of DIPGs have H3K27 mutation
85%
What % of childhood diffusely infiltrating glioma do not have H3 mutations
50%
Do childhood HGG respond to TMZ
Generally no
Only a subset have MGMT hypermethylation
H3.3 G45R/V subgroup
What are prognostic factors for HGG
max safe resection is most important
female gender does a bit better
central is bad
lateralized is good
IDH mutants do better
MGMT overexpression, PTEN mutation, P53 mutations, histone mutations are all bad
Describe the treatment paradigm
Max safe resection followed by RT
TMZ sometimes given but there is a lack of efficacy
Describe the RT doses and volumes
T1 PG+ cavity+residual disease+T2 FLAIR + 1.5-2 cm (anatomically constrained)—>CTV5040
T1PG residual disease+1 cm–> CTV5940
PTV= CTV+ 3mm
What % of pediatric brain tumors are diffuse midline brainstem gliomas
10-20% in pedes vs. 1% in adults
It is the main cause of brain tumor related death in pedes
What is the peak age for DMBG
4-6 years
What is the differential diagnosis of DMBG
ATRT
PNET
harmatoma
mets
abcess
What is the treatment paradigm
Steroids and RT ASAP
RT dose of 5400-5940 to T1 PG and FLAIR+ 1-2 cm (anatomically constrained) = CTV
PTV= CTV= 3 mm
Generally no TMZ
hyper and hypofx has not helped but can consider 44.8/16 fx or 39/13 fx
What is the median survival of pediatric midline gliomas
9-12 months
What is a LGG exophytic glioma
-A midline gioma arising from the 4th ventricle and not invading the brain stem
-Typically they are pilocytic astrocytomas
-After GTR, 10 year survival is > 75%
What age group gets choroid plexus carcinomas/papillomas
70% of patients with CPCs are under the age of 2
Where do choroid plexus carcinomas/papillomas occur in kids vs. adults
In kids they arise in the lateral ventricle
In adults, they arise in 4th ventricle
What is the workup for patients for choroid plexus carcinomas/papillomas
CSF cytology
MRI brain and total spine
Describe differences between choroid plexus carcinomas appear vs. papillomas on MRI
Papillomas- 60% are benign, WHO grade 1. Very homogenously contrast enhancing on MRI, have calcifications, appear as a well circumscribed mass within the lateral ventricle
Carcinomas- 33% present with distant mets
Heterogeneously contrast enhancing
may have hemorrhage, necrosis
usually show invasion of the brain parenchyma
What is the treatment paradigm for choroid plexus carcinoma/papillomas
Max safe resection
Can be difficult because they are friable and vascular
Chemo can be used neoadjvuantly or embolization can be done prior to surgery
chemo used- ifosdamide, carboplatin, etoposide
RT indicated if over age of 3, CPC, recurrent tumor, CSF poisitve
What is the 5 year OS for CPC vs. CPP
CPC- after GTR 80-100%; after STR- 65%
CPP-20-30%
