EBRT PLANNING OF EWINGS & OSTEOSARCOMA

1. EBRT IN EWINGS & OSTEOSARCOMA
Prarabdh Singh JR3
Akansha Anup SR1

2. FLOW OF SEMINAR
Epidemiology
Diagnostic staging & workup
Management :Chemotherapy & local therapy
RT Planning in Ewings sarcoma

3. EPIDEMIOLOGY
 2nd most common primary bone cancer
• 1 new case per 1 million population in US
• Between age 10-19 yrs incidence rises to 9-10 per million
• Whites affected twice as compared to Asians/Africans
• Male to female: 1.3:1
• Indian Incidence: Difficult to determine as rare and highly
underdiagnosed

4. S.J. Cotterill et al, JCO: 18;2000,
3108- 3114
Sites

5. • Locoregional Pain
• Palpable Mass
• Low grade Fever
• Site Specific Symptoms
• Metastatic Disease-Non Specific Symptoms(25% at
diagnosis)
• Median Duration Of Onset of Symptoms to definite
Diagnosis:3-9 months
CLINICAL FEATURES

6. WORKUP
• Routine blood inv(CBC,Biochem,Electrolytes)
• ESR
• LDH
• Radiology
• Primary Biopsy
• Bone Marrow Biopsy(BM spread in approx. 10% cases)
• Molecular Pathology/Genetics
Imaging
• X ray
• CT scan
• MRI
• Bone scan
• PET scan

8. PATHOLOGY
• Classic Ewing’s sarcoma appears as
sheets of monotonous round cells.
• Scanty cytoplasm & round nuclei with
evenly distributed finely granular
chromatin & inconspicuous nucleoli.
• Strong,diffuse membrane staining is
observed with the O13 monoclonal
antibody to p30/32MIC2 (CD99).

9. MANAGEMENT
Induction
chemo
Local RT/Sx
Maintainence
Chemo
12-24 Weeks VAC/IE AT 12/18weeks Upto 1year

11. CHEMOTHERAPY

12. EFT 2001 protocol(TMH)

13. LOCAL THERAPY
• Surgery Radiotherapy
• Types of resection: Types:
I. Intralesional Pre-op
II. Marginal Definitive
III. Wide excison Post-op
IV. Radical
Safety margin -atleast
Bone-1cm margin
Muscle/fat-5mm margin
Fascia-2mm margin

14. RADIOTHERAPY

15. Indications of Radiotherapy
Definitive
Tumors where Resection
is Impossible
For skull, face, vertebra,
or pelvic primary
where only an intra-
lesional resection is
achievable
Patient with poor
Surgical risk
Patient refusing surgery
Preoperative
Narrow resection
margin expected
Sterilize tumor
compartment
Reduce risk of
dissemination
Postoperative
For gross or microscopic
positive margin
For marginal Resection
For wide-resection with
Poor Histological
response to Neo-
adjuvant Chemotherapy
(>10% viable
tumor cells in the
specimen)
Based on CESS-81, CESS-86, EICESS-92 Studies : Schuck et al,IJROBP-1998 & 2003

16. • Gross tumor- 55-60 Gy
• Microscopic Residual Disease-50 -55 Gy
• No residual Disease(Post op poor response to chemo)-45-50 Gy
Target:
The appropriate irradiated volume is an involved field to the pretreatment tumor
volume plus 2-2.5cm margin, followed by a boost to the post-induction
chemotherapy tumor volume with margin
https://doi.org/10.1002/pbc.10472

17. Laskar S ,Mallick I. et al. Pediatr Blood Cancer 2008;51:575–
580

18. In an analysis of patients receiving PORT in the CESS 86
and EICESS trials,
Schuck et al
no significant difference in the local control and survival
who received RT within 60 days of surgery or later.
Dunst J,et al -
improved local control in CESS 86 over CESS 81
timing of RT was brought forward from the 18th week to the 10th week
Dunst J, Results of CESS 81 and CESS 86. Cancer 1991;67:2818–2825
Schuck A,. Strahlenther Onkol 2002;178:25–31.
Timing of Post-Operative Radiation

19. FIG. Changes in treatment volume. (A) Field
encompassing the entire length of the medullary cavity
for a tumor involving the proximal left humerus. (B)
Tailored field encompassing only the proximal aspect of
the leg for a limited tumor of the left tibia.

20. STEPS OF PLANNING
Positioning &
Immobilization
Planning
CT Scan
Target
Volumes
Delineation
Treatment
Planning
Process

21. CASE CAPSULE

22. 15 years female
P.w.c.o pain in right buttock region radiating to right leg since july 2019
Difficulty in walking since sept 2019
Investigations:
PETCECT(25.5.2020)
FDG avid STM involving sacrum & coccyx with erosive lesion
Low FDG avid mesentric LN anterior to right kidney
Sacrum mass bx (1.6.20)
Ewings sarcoma
Bone marrow: Uninvolved
Received 3# VIDE from 18.6.20 to L.D 25.7.20
PETCECT (2.8.20)
Low grade FDG uptake in lytic changes with STM
Plan:Definitive CTRT

23. Pre-chemo PET-CECT

24. Post Chemo Scan

25. POSITIONING
Head first supine Arms overhead, No Knee rest.
Abdo BP, 4 clamp Abdo orfit. All Outer clamps.
Fiducials placed at Pubic symphysis level
5 mm NCCT cuts taken.
Pushed to PACS.

26. PLANNING SCAN

27. CONTOURING

35. PLANNING
Dose Prescription:55.8Gy/31#
Technique:IMRT with IGRT

36. PLAN:CONVENTIONAL VS 3DCRT
 95% Isodose volume  95% isodose volume

37. PLAN:CONVENTIONAL VS 3DCRT
50% Isodose volume 50% Isodose volume

38. PLAN:CONVENTIONAL VS IMRT
95% isodose volume 95% Isodose volume

39. PLAN: CONVENTIONAL VS IMRT
50% Isodose volume 50% Isodose volume

40. PLAN:3DCRT VS IMRT
95% isodose volume 95% isodose volume

41. PLAN:3DCRT VS IMRT
50% Isodose volume 50% Isodose volume

42. PLAN :3DCRT VS IMRT
70% Isodose volume 70% Isodose volume

43. DVH

45. OAR:DVH(BLADDER)

48. DVH(RECTUM)

51. Structure Conventional 3DCRT IMRT
PTV V95%-96% 97% 96%
Bladder 55Gy 25.91Gy 23Gy
Rectum 52Gy 38.3Gy 36.1Gy
Bowel Bag 22Gy 11.4Gy 9.1Gy
Rt Femoral head 10.4Gy 7.9Gy 4.8Gy
Left femoral head 5.1Gy 3.8Gy 3.1Gy

52. CASE CAPSULE-2
12 year female
P.w.c.o swelling in forearm since 4 month
X ray Forearm(A+P):Diaphyseal expansile lesion in left leg
Bx :Ewings sarcoma
Started with EFT 2001-Good response
U/w I/C Fibulectomy on 5.6.20
HPR:88%necrosis,all margins free
Planned for Post Op RT

53. POSITIONING
 Supine ,arms by side ,Leg externally rotated
 Thermoplastic mask

54. CONTOURING

58. PLANNING
Dose prescription to tumor bed :45Gy/25#
Lung bath:12.6Gy/7#

61. LUNG BATH
Description:12.6Gy/7#

66. PROTON THERAPY

67. Retrospective review of 30 patients treated with proton therapy
between april 2003-April 2009 at Massachusetts hospital
14Male & 16female patients
Median dose:54Gy
Median F/u:38.4months
https://doi.org/10.1016/j.ijrobp.2011.03.038
3year actuarial rates
EFS 60%
LC 86%
OS 89%

69. FOLLOWUP
After completion of therapy all children shall be followed
up:
every 3 monthly for the first year
every 6 monthly for the 2nd & 3rd year
yearly thereafter
This is applicable to all patients except when
specified

70. Second malignant neoplasms
Radiation Induced Sarcoma
dose related
much less frequent < 48 Gy
Alkylator Induced Leukemia
alkylator dose more important than the addition of etoposide
Adriamycin cardiomyopathy
Ifosfamide: renal toxicity
Gonadal failure
Chronic pain/musculoskeletal dysfunction related to local therapies
Psychological Trauma - adolescents
Late Effects in ESFT Survivors

71. OSTEOSARCOMA

72. • Malignant mesenchymal tumour
• Characterized by production of osteoid matrix and woven
bone by tumor
• Molecularly:
• It is a sporadic complex genotype sarcoma, (as
distinguished from the balanced translocation- associated
sarcomas (e.g., Ewing sarcoma)): Cell cycle regulators such
as p53 and Rb have been implicated
(Li-Fraumeni, Hereditary Retinoblastoma
INTRODUCTION

73. EPIDEMIOLOGY
 Most commonly diagnosed primary malignancy of bone (Rare tumor
nonetheless
 Bimodal peak of incidence: One around adolescence and another
smaller peak in elderly (60+)
 Males affected slightly more frequently than females.

74. •Malignant spindle cells
•Osteoblasts
•Osteoid/immature bone matrix
Pathologic Classification of tumor

75. •METASTASIS:
•Disseminate through blood
•1st site – lung 9.3%
•2nd bone 3.9%
•Lymph node involvement only <10% -poor prognostic sign.
•SKIP METASTATIS:
•Located within the same bone as the main tumour but not in continuity with it.
•High grade sarcomas-develop by embolisation of tumour cells within the marrow sinusoids—
represent local micromets
•Clinical incidence -1%. Predict poor prognosis

76. •Site
•Pain and soft tissue swelling
•Night pain, no effusion in adjacent joint and movements are normal.
•Age > 40 yrs – pre existing disease
•Paget’s disease, irradiation, multiple hereditary exostosis, polyostotic fibrous
dysplasia.
•Associated syndromes-
•Li fraumeni syndrome
•Rothmund Thomson syndrome
•Werner’s syndrome

77. •CENTRAL/INTRAMEDULLARY(90-95%)
•CLASSIC(CONVENTIONAL) 75-80%-HIGH GRADE
•OSTEOBLASTIC
•CHONDROBLASTIC
•FIBROBLASTIC
•LOW GRADE
•SMALL CELL
•TELANGIECTATIC
•SECONDARILY IN ABNORMAL BONE(PAGET’S)
•SURFACE (5-10%)
•PAROSTEAL-LOW GRADE
•PAROSTEAL-HIGH GRADE
•PERIOSTEAL
•EXTRAOSSEOUS

78. IMAGING
X-RAY
 CT SCAN
 MRI
 BONE SCAN
 ANGIOGRAPHY

81. Definitive Indications
Unresectable tumor
Preoperative Indications
Adjuvant Indication
• Margin+
• Head & Neck Cancer

82. DOSE
Definitive setting:70.2Gy/39#
Adjuvant settig:64.8Gy/36#

84. CASE CAPSULE -1
(DEFINITIVE)

85. 21yrs,male ,Hailing from kolkata
p.w.c.o left anterior & lateral chest wall pain X5months
Investigations:
1)MRI Thorax
11x5.2cm lobulated chest wallmass in left & posterior chest wall with
encasement of 3rd & 6th rib underlying nodular extrapleural and overlying
extraosseous soft
tissue components at the intercostal muscles
Receive 6# of chemo
2)CT Guided bx :Chondroblastic OGS
Plan:Definitive RT

86. Pre-Chemo Scan

87. Post chemo response assesment

88. CONTOURING

91. PLANNING
DOSE PRESCRIPTION:70.2GY/39#

93. CONVENTIONAL VS 3DCRT
95% Isodose volume 95% Isodose volume

94. CONVENTIONAL VERSUS 3DCRT
50% Isodose Volume
50% Isodose Volume

95. CONVENTIONAL VS IMRT
95% OF ISODOSE VOLUME 95% OF ISODOSE VOLUME

96. CONVENTIONAL VS IMRT
50% Isodose volume 50% Isodose volume

97. DVH(COMPARISON)

99. Structure Conv 3DCRT IMRT
PTV V95-96% V95-96% V95-97%
Lt Lung 43.9Gy 28.45Gy 22.1Gy
Rt Lung 1.5Gy 5.5Gy 4.8Gy
Heart 3.9Gy 2.1Gy 1.5Gy
Spinal cord 65Gy 60Gy 44.5Gy

100. CASE CAPSULE-2 (POST OP)

101. 26 Year Female from Lucknow
H/o nasal obstruction & epistaxis in march 20
MRI 15.10.20 :Lobulated lesion in right nasal cavity with intraorbital
extension
U/w FESS +Bx--.Osteosarcoma
Received 4# Cis adria
MRI H+N:
Residual lesion
U/w endoassisted resection of sinonasal osteosarcoma
Plan:Adjuvant RT

102. IMAGING
Post op MRI

103. CONTOURING

106. PLANNING
Dose prescription: 63Gy/35#
Technique:IMRT with IGRT technique

108. CONVENTIONAL VS 3DCRT
50% Isodose volume 50% Isodose volume

109. CONVENTIONAL VS 3DCRT
95% Isodose volume 95% Isodose volume

110. CONVENTIONAL VS IMRT
95% Isodose volume 95% Isodose volume

111. CONVENTIONAL VS IMRT
50% Isodose volume 50% Isodose volume

112. DVH(COMPARISON)

114. Structure CONV 3DCRT IMRT
PTV V95%-93% 91% 92%
Left eye 66.53Gy 26Gy 10.5Gy
Right eye 23.1Gy 35Gy 22Gy
Chiasma 45.8Gy 28Gy 23Gy
Left optic nerve 28.5Gy 26.1Gy 10.5Gy
Right optic nerve 62Gy 57Gy 22.2Gy

115. THANK YOU