2. HISTORY
• 47year male
• Nonsmoker
• ECOG-1
• One episode of GTCS in the month of march 12 2020.
• Duration of the episode is for 3 to 4 min, followed by aura.
• Post ictal confusion for a duration of 15 to 20 min
• No headache and vomiting
• No history of involuntary urination or defecation.
• Another episode of GTCS in the month of June 15th 2020.
• Duration of the episode is for 2 to 3 min, followed by aura.
• Post ictal confusion for a duration of 25 to 30 min
• No headache and vomiting’s.
• No history of involuntary urination or defecation
3. • Left occipital lobe and inferior
temporal lobe.
• Lesion of size 3.2*3.2 cm
• Hypointense on T1 .
• Heterogenous on T2 .
• Brilliantly heterogenous
enhancement
• Perilesional edema present
• Occipital horn of left lateral
ventricle dilated.
• MR spectroscopy shows
increased choline and
decreased NAA.
• Possibilities :? Ganglioglioma
PRE OP MRI
7. • Left temporo-occipital region
lesion
• Post surgical defect of size
3.2*3.0cm
• Thick walled minimal irregular
outline cavity
• Central cystic
• Hypointense on T1
• Hyperintense on T2
• Bloom on wall cavity s/o
hemorrhagic products
• No perilesional edema is seen.
• Hyperintense on diffusion images
along the peripheral wall of
lesion.
POST OP MRI
8. • Brain : surgical defect in the
left parieto-occipital region
• Size 3.2*2.4cm
• Lung : spiculated lesion in the
upper lobe of right lung .
• Size 2.6*2.1 (SUV max 3.5)
• Innumerable sub centimeter
nodules in both the lungs. s/o
met
• Right paratracheal lymph node
size 1.1*1.6 (SUV max 3).
• Hypermetabolic lymph nodes
in the right paratracheal and
subcarinal region.
PET SCAN WHOLE BODY
9. • CA Right lung with brain
metastasis
• Post operative case of
the brain metastasis
• TNM staging :
cT4N2M1b
Final Diagnosis
10. Tumor board decision
• After group discussion with neurosurgeon,
radiation oncologist and medical oncologist
board decided to plan for stereotactic
radiotherapy followed by chemotherapy
• Patient was explained about complications
and outcome of the procedure
12. Patient discussion
• Discussed about the procedure
• Discussed about imaging and follow up
• Discussed about tumor response
• Discussed about need of radiotherapy in
future[WBRT/SRS]
• Discussed about post radiotherapy raised ICT
16. Time interval to address cavity dynamics
Caution must be taken when treating cavities in the early(<21 days) interval after
surgery as it may lead to irradiating more normal tissue especially in small tumors
18. Give adequate DREAM protocol before
planning image to decrease edema
Drug Dosage
D Inj. /tab DEXA 8mg Thrice a day after food 5days
R Inj. /tab Ranitidine Twice a day before food 5days
E Inj. /tab Emset 8mg Thrice a day before food 5days
A ANTIEPILEPTICS SOS
M Inj. Mannitol
Syp. Glycerol
Thrice a day infusion over 20 min
20 ml Thrice a day in apple juice
19. • Surgery date -23rd JUNE 2020
• MRI planning 17th JULY 2020 - 24th day post op
• CT planning – 21st JULY 2020 - 28th day post op
Time interval to address cavity dynamics
20. • 1mm slice
• Contrast
• Vertex to neck
• With Fraxion
• CT plan done at end
of 28th day of surgery
keeping the cavity
remodeling in mind
Planning CT
21. MRI protocol
• T1/T2/FLAIR sequence- Usual
sequence
• 3D FSPGR contrast- Normal
anatomy
• 512x 512 matrix
• 1mm slice
• No gap
• No tilt
• Neutral neck
• FOV should include
• body contour nose, eye and skull
22. Pattern of recurrence in cavity
• Cavity
• LMD-leptomeningeal spread
– Nodular pattern
– Sugarcoat pattern
• Surgical tract
• Based on histology
23.
24. • Breast cancer histology,
• Piecemeal resection of BM
• Posterior fossa location
• Multiple BM
• And hemorrhagic or cystic features
• It is thought that this increased risk is due to
tumor spillage into the cerebrospinal fluid
(CSF) at the time of surgical resection
Risk factors for LMD
25. • Nodular LMD (nLMD) was defined as new focal
extra-axial distinct nodular enhancing lesions
located on the leptomeninges or ependyma.
• Classical LMD (cLMD) was akin to “sugarcoating”
enhancement and was defined as new linear or
curvilinear enhancement of the leptomeninges
involving the sulci of the cerebral hemispheres,
cranial nerves, brainstem, cerebellar folia, or
ependyma
Types of recurrence
44. SL NO PARAMETER VALUE
1 D MAX 36.43Gy
2 D95% 31.01Gy
3 D100% 28.23Gy
4 V95% 99.99%
5 V30 Gy[V100%] 99.56%
6 V110% 44.45%
7 V120% 0.03%
8 V130% 0%
1. Prescription Isodose level is usually not 100% PD covering 100% PTV
2. Often 95% PD covering 95% PTV or higher
3. Or 100% PD covering 95% PTV or higher.
Michael Torrens,/J Neurosurg (Suppl 2)/2014
PTV coverage index
45. • FORMULA
• VOLUME OF PRESCRIPTION ISODOSE/PTV VOLUME
• 43.798/37.491=1.17
• DESIRABLE=1
[Sonja Petkovska
Proceedings of the Second
Conference on Medical Physics and
Biomedical Engineering]
RTOG conformity index
46. • FORMULA
(VOLUME OF PRESCRIPTION ISODOSE IN AREA OF INTEREST)2
PTV VOLUME X VOLUME OF PRESCRIPTION ISODOSE
• =39.764 x 39.764 /37.494 x43.798 =0.96
• IDEAL= > 0.85. AND <1
Michael Torrens,/J Neurosurg (Suppl 2)/2014
Paddick conformity index
47. • FORMULA
• MAXIMUM DOSE/PRESCRIPTION DOSE
• 36.43Gy/30Gy=1.21
• DESIRABLE = 1.1-1.3
HOMOGENITY index
48. • Dose fall off observation is very much needed in this
evaluation under headings
• Gradient index
• Difference between various isodose lines
• e.g between 80% and 60%- ideal- <2mm
• Between 80% and 40%- ideal- < 8mm
• For that reason we have to calculate equivalent
radius
Dose fall off
49. • To evaluate dose gradient we have to find out
difference between radius of various isodose line
• But none is iso spherical
• We have to find out equivalent radius from formula
• First find out the specified isodose volume
• Then calculate the radius
• V=4/3 πr3
• r= (3V/4π)1/3
Equivalent radius
51. • FORMULA
– Difference of equivalent radius of prescription
isodose and equivalent radius of 50% isodose
• 2.19mm-3.15mm=0.96mm
• It should be between 0.3 to 0.9
Gradient index
52. • BETWEEN 80% AND 60%- IDEAL-<2mm
– HERE- 0. 4mm
• BETWEEN 80% AND 40%- IDEAL- <8mm
– HERE- 1mm
EORTC-22952-26001
Distance between various isodose lines
58. SL NO ORGAN DESIRABLE ACHIEVED
1 RT. EYE MAX <22.5Gy 1.97Gy
2 LT. EYE MAX <22.5Gy 4.4Gy
3 RT. OPTIC NERVE MAX <22.5Gy 2.3Gy
4 LT. OPTIC NERVE MAX <22.5Gy 5.5Gy
5 OPTIC CHIASM MAX <22.5Gy 7.5Gy
8 BRAIN STEM MAX 23-31Gy 10.01Gy
9 RT. COCHLEA MEAN <25Gy <1Gy
10 LT. COCHLEA MEAN <25Gy <1Gy
GG HANNA/CLINICAL ONCOLOGY/2016
OAR coverage
59. • MECHANICAL ISOCENTER CHECK
– WINSTON LUTZ TEST
• POINT DOSE VERIFICATION
• TOLERANCE-1MM
Travis R. Denton/JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS/2015
QA part
63. PREMEDICATION
• TAB. DEXAMETHASONE 8MG THRICE DAILY
STARTING DAY BEFORE
• TAB. ONDANSETRON 8MG THRICE DAILY
STARTING DAY BEFORE
• TAB. PAN 4O ONCE DAILY STARTING DAY
BEFORE
• DIABETES CARE IF
Pre medication-optional
64. • TAPER THE STEROID OVER A WEEK
• ANTI EMETICS
• PPI
Post medication-optional
66. DOCTORS
• DR P S BHATTACHARYA
• DR C R KUNDU
• DR V K REDDY
• DR P MADHURI
PHYSICISTS
• MR A C PRABU
• MR A SRINU
• MR Prasad
• DR ANIL KUMAR
TECHNOLOGIST TEAM
Acknowledgments