CNS Flashcards
RPA class
- I - AA, age<50, KPS>70
- II - AA, age >50, KPS>70
- III: GBM <50 yrs KPS>90 MS 18mo
- IV: GBM <50 yrs KPS<90 MS 11mo
- V: GBM >50 yrs KPS>70, MS 9 mo
- VI: GBM >50 yr, neuro deficit, KPS<70, MS 5 mo
GBM treatment
Clinical trial
Max safe resection -> RT 60/2 Gy with concurrent TMZ -> adjuvant TMZ starting 1 month after RT
-concurrent TMZ dose: 75mg/m2/day x 7 days/wk
-adj dose starting 1 month after RT: 150mg/m2/day x 5 days/28 days x 6 mo
(Zofran and Bactrim MWF PPX w/ TMZ)
-take TMZ night before per Stupp
GBM elderly
<70 yrs KPS high -> Stupp regimen
>70 yr wih KPS good -> TMZ + 40 Gy/15 fx – concurrent and adjuvant TMZ. (mMGMT was predictive) *>65 and ECOG 0-2*
KPS fair -> TMZ alone if MGMT methylated
-> RT alone if MGMT unmethylated (40/15 or 25/5 [Roa])
KPS very poor -> supportive care only
GBM planning objectives and constraints
> 95% of PTV receives 100% of dose
Min dose to PTV 90%
Brainstem < 54 Gy (max 60 to <10 cc)
Optic chiasm/nerve < 54 Gy
Spinal cord/Retina < 45 Gy
Cochlea Dmean < 45 Gy
Lens < 10 Gy
Lacrimals < 26 Gy
GII-III IDH wildtype treatment
treat like GBM
G2 Astro treatment and OS
MSR ->
Low risk -> observe
High risk -> 54 Gy (T2/T1gad/cavity + 1cm) -> PCV
6y
LR: <=40y and GTR
G3 Astro treatment and OS
MSR -> 59.4 Gy (T2/T1gad/cavity + 1.5cm) -> TMZ
5y
G2 Oligo treatment and OS
MSR ->
Low risk -> observe
High risk -> 54 Gy (T2/T1gad/cavity + 1cm) -> PCV
14y
LR: <=40y and GTR
G3 Oligo treatment and OS
MSR -> 54 Gy (T2/T1gad/cavity + 1cm) -> PCV
14y
Meningioma pathology
psammoma bodies
- Benign (75-85%) – Grade I: <4 mitoses / 10 HPF
- Atypical (5-10%) – Grade II: 4-19 mitoses/ 10 HPF, or Brain invasion
- Anaplastic (<5%) – Grade III: >=20 mitoses / 10 HPF
Grade 1 Meningioma Man
Grade 1 (benign):
Asx and < 3 cm: observe
-median growth 4 mm/yr
Sx, large, high risk area, progressing
- Surgery – consider post-op RT if STR (but mostly observe)
- Definitive RT to 54 Gy
- Definitive SRS to 12 Gy
CTV is 1 cm along dura for Grade 1, 2-3 cm for Grade 2/3
Grade 2 Meningioma Man
Grade II (atypical):
Surgery -> RT
If GTR, RT to 54 Gy (could observe if good surg salvage option)
If STR, RT to 60 Gy (RTOG 0593)
CTV is 1 cm along dura for Grade 1, 2-3 cm for Grade 2/3
Grade 3 Meningioma Man
Grade III (anaplastic): Surgery -\> RT to 60 Gy
No SRS for G2-3
CTV is 1 cm along dura for Grade 1, 2-3 cm for Grade 2/3
Simpson grade resection
Simpson grade resection (1-3 is GTR, 4-5 is STR)
I – GTR removal bone/dura
II – GTR dural coag
III – GTR no dural coag/removal
IV – STR
V – Decompression only
**new addition of a grade 0- stripping of 2-4 cm of dura
SRS constraints
SRS:
Optic chiasm: 8 Gy need 3mm to do this
Whole brain – GTV V12 < 5-10cc
Brainstem < 12 Gy
Eye/retina: 8 Gy
Cochlea: 4 Gy
Pit Adenoma Treatment
Non-functioning:
No role for UPFRONT RT unless inoperable!!
Non-functioning:
Trans-sphenoidal surg (TSS)
-adj RT at 6 wks if STR or growth
EBRT 45 Gy
SRS: 15 Gy
Pit Adenoma Treatment
ACTH or GH
No role for UPFRONT RT unless inoperable!!
ACTH or GH: TSS
-adj RT for persistent hormone secretion post-op or STR
EBRT 50.4 Gy
SRS: 25 Gy
Pit Adenoma Treatment
TSH-secreting
No role for UPFRONT RT unless inoperable!!
TSH-secreting:
TSS -> post-op RT always (54 Gy)
Pit Adenoma Treatment
Prolactinoma:
No role for UPFRONT RT unless inoperable!!
Prolactinoma: medical management (bromocriptine) first even if visual sx. Surgery for failure of medical tx.
Inoperable: RT
Recurrence after surgery: RT
AN treatment
1) EBRT or SRS
both offer > 90% LC
60-70% hearing preservation (may be lower w/ SRS)
EBRT dose: 50.4/1.8 Gy (>3 cm, useful hearing, malignant (54 Gy), NF2, pressing on brainstem)
SRS dose: 12 Gy
SRT doses:
7 Gy x 3 (Stanford)
5 Gy x 4-5 (Slotman)
2) Microsurgery (translabyrinthine or middle cranial fossa or subocipital)
50% useful hearing
3) Observation: tumors grow 1-2 mm/year, so observation is always an option in someone who has already lost their hearing
AVM dose and success
< 3 cm: 20 Gy to 50% IDL
> 3 cm: 16 Gy to 50% IDL
Target is nidus, not feeding arteries or draining veins
For tumors >15 cc, consider staged SRS 6 months apart
Obliteration rate 80-90% with SRS (especially if <10cc)
Median time 1-3 yrs for complete obliteration
Risk dec by 50% during latency period
Trigeminal Neuralgia dose
80 Gy max; target is trigeminal nerve root; single 4 mm isocenter; brainstem edge at 20-30% IDL
Chordoma dose
Max safe resection -> RT
Dose: 70 Gy (refer for protons for BOS location)
HA- WBRT
HA-WBRT: 3 Gy x 10
-brain target: brain – hippocampus + 5mm, no PTV
-contour all mets – not required
-contour hippocampus + 5 mm margin
-hippocampus is grey matter
-RCT CC001 – iimproved cognitive outccomes with HA-WBRT over traditiional WBRT – ineligible if SCLC, mets within 5 mm of hippocampus, lepto
-hippocampus: max < 16 Gy, D100%<9Gy
-optics <37.5
**who gets this?
HA-WBRT+memantine:
Phase III trial of WBRT+memantine +/- HA
*HR for NCF 0.74, lower risk exec function at 4 month, encoding and consolidation at 6, pt reported faigue, speaking, and memory improved 6 months.
SRS dose
≤2cm: 24 Gy (20 Gy)
- 1-3 cm: 18 Gy
- 1-4 cm: 15 Gy (or 6 Gy x 5)
