This document provides an overview of the approach to prostate SBRT planning. It discusses the evidence supporting SBRT, patient selection, immobilization techniques, imaging protocols, target delineation guidelines, dose selection, planning constraints, quality assurance procedures, and peri-treatment management. The key advantages of SBRT for prostate cancer are the short treatment time of 5 fractions, high biological effective dose achieved, and comparable oncologic outcomes to other EBRT techniques with side effects that are earlier but also resolve sooner. Careful planning and quality assurance throughout the process are emphasized.

1. APPROACH TOWARDS
PROSTATE SBRT PLANNING
DR KANHU CHARAN PATRO
MD,DNB(RADIATION ONCOLOGY),MBA,FICRO,FAROI,PDCR,CEPC
HOD,RADIATION ONCOLOGY
Mahatma Gandhi Cancer Hospital And Research Institute,
Visakhapatnam, India
drkcpatro@gmail.com /M+91-9160470564
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2. Slow my flow
1. Introduction
2. Evidences
3. Bladder and bowel management
4. Simulation
5. Imaging
6. Target delineation
7. Dose selection
8. Constraints
9. Planning
10. QA
11. Daily delivery
12. Post medication
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3. 1.Introduction
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4. Introduction
• The radiobiology of PCa with its low α/β-ratio and the slow cell proliferation
are considered to make PCa sensitive to a high dose per fraction and thus
hypofractionation advantageous, especially in terms of radiobiological
efficacy.
• Various fractionation schemes have been reported in SBRT literature, but
the optimal total dose and dose per fraction are still unknown
• The use of ultra-hypofractionated (≥ 5 Gy / fraction) external beam
radiotherapy (EBRT) is emerging as the primary treatment modality in
clinically localized prostate cancer (PCa).
• It can be delivered as stereotactic body radiotherapy (SBRT) by using an
image guided robotic[Cyber-KNIFE] or a gantry-based [LINAC-X-KNIFE]
device
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5. Treatment
protocols
Immobilization as available[knee
rest/vaclok/mask]
Alternate day treatment
CT simulation day and every treatment day
enema
CT simulation day and every treatment day
bladder filling procedure
Daily CBCT
Give some steroid during treatment day and
tapper
IPSS score will increase during treatment
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6. 2.Evidences
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7. 11/6/2022 7
SHARP CONSORTIUM
PACE A
PACE B
PRIME
NRG GU 005
HYPO RT- PC
PATRIOT
ASCENDE-SBRT
HEAT KRISHNAN et.al

8. 11/6/2022 8

9. Patient Selection
• Current evidence for SBRT in prostate cancer relates mainly
to patients with low and intermediate-risk disease, with
selected cases of high risk PCa although definitions may vary
between studies.
• Long term series with excellent local control and minimal
toxicities very convincing for SBRT. (Katz et al, King et al
Pooled Analysis, Kishan et al, SHARP Consortium)
• IPSS score less than 10
• No TURP
• Ongoing studies for High Risk, Very High Risk and Node
Positive Prostate Cancer.
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10. 11/6/2022 10

11. 0
Lancet Oncol 2022 Published Online September 13, 2022
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12. IPSS SCORE
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13. PRIME TRIAL
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14. IS MOTION MANAGEMENT REQUIRED?
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15. 3.Bladder and
bowel
management
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16. 11/6/2022 16

17. RECTUM protocol
• Soap water enema
• Enema Before planning CT
• Enema Before each treatment
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18. Bladder protocol
• Empty bladder
• Drink 750 ml water
• Wait half an hour
• CT/TREATMENT
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19. BOWEL- BLADDER CHART
DATE ENEMA BALDDER EMPTYING AND
DRINKING 750 ML TIME
TREATMENT
TIME
INTERVAL
CT YES
D1 YES
D2 YES
D3 YES
D4 YES
D5 YES
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20. 4.IMMOBILIZATION
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21. SIMULATION
SUPINE
• NIL/
• VACLOCK/
• SBRT BOARD
WITH OR WITHOUT KNEE REST
HANDS ABOVE HEAD
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22. FRAME LESS SBRT
IMMOBILIZED THE VAC-LOK WITH INDEXER
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23. 11/6/2022 23

24. 5.Imaging
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25. STEP BY STEP ANALYSIS
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COSID INDEX
C COVERAGE INDEX
O OAR INDEX
S SPILLAGE INDEX
I IMAGING INDEX
D DELIVERY INDEX
Kanhu et.al/J CURR ONCO/2022

26. IMAGING
PROTOCOL
SUPINE WITH KNEE REST
DESIRABLE FULL COMFORTABLE BLADDER
EMPTY RECTUM
AXIAL CECT [Arterial and delayed phase-10 min]
T2 MRI 3 PLANE [A/C/S]
2-3 mm slice
UPPER BORDER OF KIDNEY TO MID THIGH
ANAL VERGE MARKER
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27. IMAGING
• CECT PELVIS
• MULTIPARAMETRIC MRI
• PSMA
DIAGNOSTIC
• CECT PELVIS
• T2 MRI
FOR TARGET
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28. PLANNING CT
• 3mm slice
• Contrast enhanced CT and delayed scan CT
• Nipple to mid thigh
• With VAC-LOK + KNEE REST
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29. PLANNING MRI
• 3mm slice
• T2 MRI
• True Axial
• L5 to mid thigh
• With VAC-LOK + KNEE REST
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30. DELINEATION OF ISCHIOPUBIS FOR
FUSION
FUSE AROUND ONLY PROSTATE AREA
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31. CT MR FUSION
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32. 6.Target delineation
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33. MRI
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34. ESTRO ACROP Guidelines
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35. ESTRO ACROP Guidelines
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36. TARGET
PROSTATE
SEMINAL VESICLES
NODES SOS
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37. Looks very simple but
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38. ABCDEF OF PROSTATE CONTOURING
A
• ANI-LEVATOR ANI
B
• BULB-PENILE BULB,
• BLADDER BASE
C
• CANAL-ANO RECTAL
CANAL
D
• DIAPHRAGM-
GENITOURINARY
DIAPHRAGM
• DEFERENT DUCT
E-EXTRA
STRUCTURES LIKE
• NEUROVASCULAR
BUNDLE
• URETHRA
• VENOUS PLEXUS
OF SANTORINI
F-FIBROMUSCULAR
STROMA
FIBROMUSCULAR
STROMA
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39. TARGET DELINEATION
• CTV P: according to ESTRO ACROP guidelines
• CTV N:
• Contoured by giving a radial margin of 5 to 7mm around the common iliac, external iliac,
internal iliac, presacral and the obturator vessels and editing from muscles and bones
• Cranial extent of CTV nodes: at the level of L5–S1 vertebra
• Caudal extent: at the level obturator nodes
• Seminal vesicle: 1.5cm when no involvement; entire SV if involved
• PTV P & PTV N:
• 5mm to the CTV P (including SV) and CTV N. posterior 5mm
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40. PRESACRAL NODE
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41. Delineating obturator nodes
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42. NODAL CORONAL VIEW
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43. PTV PRIMARY_36.25Gy
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44. PTV NODE_25Gy
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45. OAR
BOTHERING BOWEL
FARLY PLACED FEMORAL HEAD
BUBBLING BLADDER
IRRITAING ANAL RECTUM
UNKNOWN URETHRA
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46. 7.Dose selection
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47. Why only 36.25Gy? Any specific reason?
If the α/β of prostate cancer is as low
as 1.5, then SBRT dose of 36.25 Gy in
5 fractions has a biologically effective
dose (BED) of 211 Gy, which is higher
than 78 Gy in 39 fractions (BED 182
Gy), but has a slightly lower BED (124
Gy vs 130 Gy) in terms of late rectal
toxicity, assuming an α/β of 3.
SLIDE FROM Dr ABHILASH
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48. DOSE SELECTION
DOSE :
36.25Gy in 5# to the Prostate
30Gy in 5# to the Gross node
25Gy in 5# to the Elective nodal region
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49. DOSE
PROSTATE
• 36.25Gy IN 5 #
NEGATIVE NODE
• 25Gy IN 5 #
POSITIVE NODES
• 25Gy IN 5 #
• GROSS NODE
30-35Gy IN 5 #
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50. 8.
OAR constraints
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51. DOSE CONSTRAINT – PRIME PROTOCOL
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52. 11/6/2022 52

53. 9.Planning
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54. PLANNING
• VMAT /VMAT SIB
• DCARC
• 3DCRT
• IMRT
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55. BEAM ARRANGEMENT
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56. PTV COVERAGE
PRIME
PROTOCOL
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57. DVH
PTV 36.25
PTV 25
RECTUM
BLADDER
BULB
BOWEL
FEMURS
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58. Prostate only SBRT
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59. PROSTATE + NODE SBRT
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60. PLAN EVALUATION
Contours
Beams
Coverage
Heterogeneity
Organs at risk
Prescription
VMAT Plan Cyberknife Plan
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61. COSID INDEX
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62. 10.QA
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63. DRY RUN
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64. 11.SET-UP VERIFICATION
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65. SET-UP VERIFICATION
• HEXAPOD CORRECTIONS
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66. DAY 1
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67. DAY 2
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68. DAY 3
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69. DAY 4
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70. DAY 5
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71. 12.Peri-medication
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72. IPSS-PRE HT
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73. IPSS-PRE RT
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74. IPSS-POST RT
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75. PREMEDICATION
TAB. DEXAMETHASONE
8MG THRICE DAILY
STARTING DAY BEFORE
TAB. PAN 4O ONCE
DAILY STARTING DAY
BEFORE
DIABETES CARE IF
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76. POST MEDICATION
Taper the
steroid over a
week
Proton pump
inhibitor
Tab
Toluteredine
4mg BD
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77. SBRT PLAN EVALUATION SHEET
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78. Summary
SBRT is an excellent treatment modality for localized prostate cancer
endorsed by ASTRO, ASCO, AUA, NCCN
Relatively short follow-up time in prospective studies and few high-risk
patients included in the trials are limitations of this technique
While oncologic outcomes appear to be comparable with other EBRT
techniques, side effects occur earlier but resolve sooner
Careful patient selection is needed
Technological advances: image-guided radiotherapy, Space OAR,
fiducial markers, MRI-based radiotherapy and robotic SBRT if possible
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79. SURGICAL REPORT- NCDB DATABASE
• V-VESCICLE INVOLVEMENT
• E- EXTRACAPSULAR EXTEANSION
• N-NODE POSITIVE
• O-OVIBIOUS PERSISTANT ANTIGEN
• M-MARGIN POSITIVE
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MORE THAN HALF OF PATIENTS

80. WHY DOUBLE TROUBLE?
• Most of the post op prostate
patients require radiation
• Why we should choose surgery,
where SBRT 5 days treatment
is available
• It is double trouble when we
add radiotherapy after surgery
as dual toxicity.
• We can complete the
treatment before their
preanaesthetic evaluation
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81. Thank you
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