CNS Low Grade Gliomas Flashcards
What grade is diffuse astrocytoma?
Grade 2
Can grade 1 astrocytoma undergo malignant transformation?
No
Is grade 1 astrocytoma commoner in adults or children?
Children (rare in adults)
Name 3 locations grade 1 astrocytomas commonly occur?
Optic nerve
Hypothalamus
Cerebellum
How much enhancement do low grade astrocytomas show on MRI with gadolinium?
Little or none
What grade is anaplastic astrocytoma?
Grade 3
How do you know an MRI is a FLAIR sequence?
Signal from CSF supressed
Enhancement on a scan means (in general terms, 1 word)
Leakage
Restricted diffusion on scan does it mean there is high or low cellularity?
High
Two types of glioma that NEVER show IDH mutations?
(1) Grade 1
2) primary GBM (ie has not arisen from a low grade glioma
Which chromosomal hallmark is associated with oligodendroglial pathology?
1p19q loss
What does 1p19q loss mean for chemo sensitivity and prognosis?
chemo sensitive
Good
Most common IDH1 mutation which codon?
132 (accounts for 80% of IDH mutations)
What molecular marker is a marker of astrocytic behaviour?
ATRX Loss
A low grade glioma has IDH wild type, what does this mean?
Bad prognosis,
Behaves like grade 4
Two molecular markers in a low grade glioma which mark it out as good prognosis?
IDH Mutation
And
1p19q loss
Can 1p19q loss and ATRX loss co exist?
No mutually exclusive
Name the 5 poor prognostic factors for low grade gliomas
Age more >= 40 Histology Astrocytic Big tumour >=6cm Crosses midline or shifting Pre op neurological deficit
2 high risk
Evidence for resecting low grade gliomas?
There are no RCTs but case series indicate that gross total resection is likely to be beneficial
Adjuvant DXT for low grade glioma- what is the benefit of immediate v wait until progression?
PFS is shorter but NO OS advantage
In high risk low grade glioma what was the OS for the RTOG9802 study of post op dxt v dxt plus 6 cycles PCV?
OS 13.3 yrs v 7.8 years favouring adding PCV
A patient has had a low grade glioma resection name 2 factors that would make you give adjuvant chemo and DXT?
Either
Age less than or = 40
Or
Subtotal resection
A patient has had a LGG resected age 56. What further treatment would you offer them?
DXT 54 Gy
Followed by
PCV 6 cycles
What is PCV chemo?
Procarbazine
CCNU (lomustine)
Vincristine
What is the other name for lomustine?
CCNU
Management of grade 4 glioma
Debulk if possible
DXT with concomitant Temozolamide 75mg/m2 daily
Adjuvant TMZ 150mg/m2
What is the difference in mgt between grade 3 and grade 4 glioma
Grade 4 everyone gets chemo TMZ plus DXT
Grade 3 DXT then if 1p19q deleted get PCV up to 6 cycles adj
