This document provides an overview of breast contouring and radiotherapy treatment planning for breast cancer. It discusses contouring the clinical target volume (CTV) and planning target volume (PTV) for the breast or chest wall as well as lymph nodes. It also outlines dose volume histogram constraints for organs at risk. Various radiotherapy techniques are described including 3D conformal radiotherapy, forward planned intensity-modulated radiotherapy, volumetric modulated arc therapy, and prone positioning. Overall, the document provides guidance on delineating targets and organs at risk and generating optimized treatment plans for breast cancer patients.

1. BREAST CONTOURING
PRESENTER:
 DR. RITURAJ
 DR. NAVAUDHAYAM
MODERATOR:
 DR. RITESH
10 August 2017

2. TREATMENT OVERVIEW
• EARLY BREAST CA (T1 T2 N0 N1)
• SX (BCS/MRM) ± CCT ± RT ± HT
• LOCALLY ADVANCED
• MRM + CCT + RT ± HT
• NEOADJUVANT CCT + SX (MRM/ BCS) + RT ± HT
• METASTATIC (M1)
• PALLIATIVE CCT/ PALLIATIVE RT/ ± HT
• ± SX
MRM (N0) – No RT
MRM (N1) – RT to CW + SCF
BCS
•WBRT + Boost
•APBI
N1 – RT to SCF
MRM – RT to CW + SCF
BCS - WBRT + Boost + SCF

3. INDICATIONS OF RT
• Indications of Whole Breast RT
• All patients after BCS
• Indications of Chest Wall RT
• N2-N3 disease
• High risk patients with N1 disease (1-3 LNs)
• Locally advanced breast ca

4. INDICATIONS OF LOCO-REGIONAL RT
• Supraclavicular LNs
• Clinical/Pathological N2 or N3 disease
• 1–3 +LN with high risk features (N1)
• Node + sentinel lymph node with no dissection unless risk of additional axillary disease is very small
• High risk, no dissection
• Axillary LNs
• N+ with extensive ECE or soft tissue deposits or Heavy nodal burden
• SN+ with no dissection
• Inadequate axillary dissection
• High risk with no dissection
• Internal Mammary: Individualized but consider for:
• Positive axillary nodes with central and medial lesions
• +SLN in the IM chain

5. TARGET STRUCTURES
• CTV Breast and Tumor Bed
• Axillary Lymph nodes
• Supraclavicular Lymph Nodes
• Internal Mammary LNs
OARS
• Contralateral Breast
• Lung – I/ L and C/L
• Heart (including LAD)
• Spinal Cord
• Brachial Plexus
• Esophagus
• Thyroid

6. AVAILABLE GUIDELINES
• RTOG (EBC and LABC)
• ESTRO (EBC) – Less liberal margins
• DBCG (EBC)
• RADCOMP Consortium
• PROCAB guidelines (Vessel based nodal contouring)

7. WHY WIRES AROUND BREAST?
• Large differences are reported b/w CTV localization using standard anatomic
borders, palpation and USG
• Hurkmans et al* - study in 2001
• Palpable breast glandular tissue was marked by lead wire before Planning CT in 6 pts
Vs. 4 patients without lead wire
• CTV was delineated by 4 RO
• Interobserver variation in volume was decreased by a factor of 4 on scans with lead
wire
• Deviations in PTV extent were greater in Posterior, Cranial and medial directions
*IJROBP Vol 50 No5, 2001

9. A word of Caution- Individualization!!!
 Guidelines serve as base on whichCTV can be individually adapted
 Encompass primary tumor bed adequately , including relevant margins around it
 In patients with tumours placed too medially/ laterally one needs to modify
conventional borders
 Apply wires carefully even on opposite breast as you keep comparing your contours
with opposite breast
 Not applicable forT/t in prone position
 All Contours are shown- does not mean that all volumes have to be treated

10. CTV Breast

11. ■ Cranial
- Uppermost level of palpable/ visible Breast
tissue
- Maximally up to inferior edge of
sternoclavicular joint (G)
-
■ Caudal
- Most Caudal CT slice with visible breast
tissue (G)
- In obese patients, positioned more ventrally
in the caudal part of breast due to
abdominal wall fatty tissue (G, ESTRO)

12. ■ Dorsal
- Pectoral muscle or intercostal ms where
there is no P Major
- Include chest wall also in LABC
■ Ventral
- 5mm under skin (G, ESTRO)
- In cases with T4b,c,d cancer where full
dose up to skin is advised: bolus may be
added (G, ESTRO, RTOG)

13. ■ Medial
- Clinical Reference / Wire
- Maximal to edge of sternum
■ Lateral
- Most difficult to delineate ( varies
according to breast ptosis)
- Traditional: Mid Axillary Line or 1.5-2 cm
beyond palpable breast tissue
- Medial to lateral thoracic A, Breast fold
(G, ESTRO, DBCG)
- Exclude Lats Dorsi ms.

15. ■ CTV Chest Wall
- Place radio opaque wires around imaginary-
original site of breast and also on MRM scar
- Generally same as breast
■ Dorsal-
– RTOG guidelines- Rib Pleural interface
(including ribs, IC ms and pectoralis ms)
– ESTRO- Unless invasion was demonstrated
(tumor stage T4a-c), no reason to routinely
include major pectoral muscle and ribs
– - Impacts Lung and Heart Doses!

16. ■ Ventral
- RTOG- Skin
- ESTRO- 5 mm under skin surface
- Skin Bolus of 3-5mm may be applied for
very thin CW (ESTRO is only for EBC)
- Inflammatory breast cancer- Up to skin
- Bolus for all fractions

18. Borders Cranial Caudal Anterior Posterior Lateral Medial
Breast
(EBC)
-Uppermost
palpable/visibl
e breast tissue
-Max: till head
of clavicle
Clinical
reference +
1-2 cm below
breast tissue
Skin Excludes
pectoralis
muscles,
Chest wall
muscles, ribs
Clinical
Reference +
Mid axillary
line typically,
excludes
latissimus
dorsi
Sternal-rib
Junction , Shouldn’t
cross midline
Breast +
Chest wall
(LABC, Post
NACT)
Same Same Same Includes
pectoralis
muscles,
Chest wall
muscles, ribs
Same Same
Chest Wall
After
mastectom
y
Caudal
border of
the
clavicle
head
Clinical
reference+
loss of CT
apparent
contralateral
breast
Same Rib-pleural
interface.
(Includes
pectoralis
muscles,
chestwall
muscles,
ribs)
Clinical
Reference/
mid axillary
line typically,
excludes
lattismus dorsi
Sternal rib
junction Medial
extent of
mastectomy scar
should typically be
included

19. Lumpectomy GTV
1. Include seroma cavity
2. Include all surgical clips when present
3. Use pre-operative imaging
4. Pre-operative and per-operative clinical findings
5. Architectural changes in planning CT

22. PLANNING TARGET VOLUME
■ Isotropic PTV Margin of 1-1.5 cm (depending on institutional protocol)
– Adequate margin in air is required for field shaping and to define edges of MLCs
■ Breast PTV Eval
– A substantial part of the Breast PTV often extends outside the patient, and is not a part
of dosimetric calculations
– Anteriorly exclude the part outside the patient and the first 3-5 mm of tissue under the
skin (in order to remove most of the build up region for the DVH analysis)
– Posteriorly no deeper to the anterior surface of the ribs (excludes bony thorax and
lung).
– It is used for DVH constraints analysis.
– Breast PTV Eval cannot be used for beam aperture generation.

26. NODAL CONTOURING

27. Supraclavicular LNs
Cranial RTOG -Caudal Edge Cricoid Cartilage
PROCAB -Cranial Edge of Subclavian A Arch
Caudal RTOG-caudal edge of Medial head of Clavicle
Junction of Brachiocephalic V and Axillary V
Medial Exclude thyroid and trachea
Medial Edge of Int carotid A and IJV
Lateral RTOG- Cranially- Scalene ms
Caudally- Junction of first rib and clavicle
DBCG- Medial edge of P Minor and Clavicle
Ventral SCM, Clavicle, 5 mm below skin
Dorsal Cranially- Posterior to ICA and Anterior to
scalene medius ms
Caudally- Lung

34. Axilla
■ Can be contoured as a single structure, as contouring each level separately can be
time consuming and often can’t be demarcated clearly from each other.
Cranial P. Minor inserts into coracoid
Caudal P. Major inserts into ribs – 4-5th Intercostal space
Ventral Laterally: Anterior surface of P. major
Medially: Posterior surface of P. major/ Ant surface of P. minor
Dorsal Ribs/Intercostal muscles/Subscapularis
Medial Thoracic Inlet
Lateral Medial border of Latissimus dorsi

36. OARS
■ Heart
– Contoured below pulmonary trunk bifurcation
– All mediastinal tissue below this level should be
contoured including great vessels
■ Coronaries: Left anterior descending artery
– Proximal 1/5th of the vessel, from the end of the left
main coronary artery passing anteriorly behind the
pulmonary artery
– Mid 2/5th of the vessel descending anterolaterally in the
anterior interventricular groove
– Distal 2/5th of the vessel running in the interventricular
groove and extending to the apex
■ Brachial Plexus

37. 1. Identify and contour C5, T1, and T2.
2. Identify and contour the subclavian and axillary neurovascular
bundle.
3. Identify and contour anterior and middle scalene muscles from
C5 to insertion onto the first rib.
4. To contour the brachial plexus OAR use a 5-mm diameter paint
tool.
5. Start at the neural foramina from C5 to T1; this should extend
from the lateral aspect of the spinal canal to the small space
between the anterior and middle scalene muscles.
6. For CT slices, where no neural foramen is present, contour only
the space between the anterior and middle scalene muscles.
7. Continue to contour the space between the anterior and middle
scalene muscles; eventually the middle scalene will end in the
region of the subclavian neurovascular bundle.
8. Contour the brachial plexus as the posterior aspect of the
neurovascular bundle inferiorly and laterally to one to two CT
slices below the clavicular head.
9. The first and second ribs serve as the medial limit of the OAR
contour.

38. Dose Volume Histogram
■ Evaluate both CTV and PTV
PTV Coverage D95 Dmax
Desirable 95% 107%
Acceptable 90% 115%

39. OARs Tolerance End Point
Ipsilateral Lung Dmean < 7-13 Gy
V20 < 20-25 %
(or <30-35% if SCF included)
V5 < 50 %
10% Symptomatic pneumonitis
20% Symptomatic pneumonitis
Contralateral Lung Dmean < 7 Gy
V5 < 10-15%
5% Symptomatic pneumonitis
Contralateral Breast Dmean < 2 Gy Dermatitis
Heart Dmean < 26 Gy
V25 < 10%, V20 < 10% (DBCG)
<15% Pericarditis
<1% Mortality
LAD V20 = 0% --
Spinal Cord Dmax < 45 Gy <0.2% Myelopathy
Brachial Plexus Dmax < 54 Gy <5% Brachial plexopathy
Liver Dmean < 30 Gy <5% Classic RILD
Esophagus Dmean < 34 Gy
V35 < 50 %
Grade 3+ esophagitis
Thyroid V45 < 100% 8% Clinical hypothyroidism

40. Hypofractionation
Conventional Hypofractionated
Ipsilateral Lung V20 V16
V10 V8
V5 V4
Heart V25 V20
V20 V16

41. Plan Generation

42. • Conventional tangents with simple or customized shielding
• Photon based
 3DCRT: wedges, MLCs for shielding heart, overdose volume
 Forward plan IMRT (Field in Field)
 TomoTherapy
 TopoTherapy (TomoDirect)
 Arc therapy (VMAT)
 Flattening filter free planning
 Inverse plan IMRT
• Electron based
 IMRT (prevents low dose exposure of C/L lung & breast)
 Electronic compensation (lowest no of MUs & planning time)
• Proton IMRT

43. Tangents

45. ENHANCED DYNAMIC
WEDGE ( 15˚)
Dmax– 108.8%
PHYSICALWEDGE (15˚)
Dmax- 110 %

46. Field-in-
field
technique:
Forward
IMRT
• Modified bi-tangential portals
• Medial and lateral tangents are first planned and dose
distribution noted.
• Use of multiple segments inside each tangential portal
• Areas of high dose are then delineated.
• A new field is created within the existing tangential
field with an appropriate MLC configuration so as to
reduce the inhomogeneity in these areas.
• These fields are finally fused by the treatment planning
system.
• ?? Possible improvement in the cosmetic outcome

57. VMAT • Novel extension of IMRT: modulation of dose rate,
gantry angle and MLCs
• Optimized three-dimensional (3D) dose distribution
may be delivered in a single gantry rotation
• Reduction in treatment MUs (30%) and delivery time
(55%) due to high dose rates (as compared to cIMRT)

59. VMAT • Novel extension of IMRT: modulation of dose rate,
gantry angle and MLCs
• Optimized three-dimensional (3D) dose distribution
may be delivered in a single gantry rotation
• Reduction in treatment MUs (30%) and delivery time
(55%) due to high dose rates (as compared to cIMRT)
• Arc treatment: Larger low dose scatter-Contralateral
breast, lungs, heart
• It is becoming evident that even small doses to the
heart and contralateral breast during radiotherapy
course are important in the long term outcomes of
breast cancer patients1
• Dosimetric advantages ofVMAT not confirmed for
patients requiring adjuvant RT to breast only2
1Darby et al. Risk of ischemic heart disease in women after radiotherapy for breast cancer. N Engl J Med 2013
2Badakhshi et al, BJR 2013

60. Is IMRT really the answer?????

62. VMAT based plan with Short tangential arcs
Anusheel Munshi et al. Short tangential arcs inVMAT based breast and chest wall radiotherapy lead to conformity of the breast
dose with lesser cardiac and lung doses: a prospective study of breast conservation and mastectomy patients (n=153)

63. • Tried to gain from both the
worlds: using classical tangential
field arrangement and at the same
time usingVMAT fields albeit with
arc length limited to 30°.
• Even though theVMAT technique
required more MUs as compared
with the other two techniques, it is
still preferable as the treatment
delivery time is very short.

64.  VMAT technique consistently scored lower values for all the evaluated parameters for the heart
(D2cc,V20Gy,V30Gy andV40Gy) except for its mean dose.
 VMAT plans were preferable over other plans in terms of PTV highest conformity and lowest
heterogeneity. Both FIMRT andVMAT techniques produced comparable plans in terms of PTV
coverage and OAR doses except for the heart.
 However, FIMRT is a labour-intensive technique requiring longer treatment planning time.
Besides, the outcome of FIMRT plan strongly depends on the personal expertise of the planning
physicist or the planning dosimetrist. On the other hand,VMAT plans were relatively simpler to
generate facilitated by readily available standard templates from plan library, requiring only
minimal changes during the optimisation depending on the individual patient anatomy.

65.  PRONE position
• Dosimetric advantages---
 More homogenous dose
 Less lung dose
• Disadvantages---
 Setup reproducibility poor
 Pt. tolerance of prone position
 Retrospective reviews have
shown excellent long term
disease control as standard
supine tangents
Particularly useful in HypofractionatedWBI ( Preferred in MSKCC )

66. What is the
Optimal
Beam
Arrangemen
t for IMRT?
• TANGENTS!!!
• Less low dose: Lung, Heart, Contralateral Breast
• Adequate coverage ofTarget volume
• Early Breast Cancer women: Do survive long… to see
the long tem effects of scatter dose

68. THANK YOU
IRCH Practice

69. Whole
Breast RT
1. Tangents withWedges
2. Tangents with Field-in-field technique
3. IMRT/VMAT : Not preferred

70. Tangent with wedges

71. Tangent with wedges: Dose
Colorwash

72. Tangents with Field-in-field

74. Tangents with Field-in-field: Dose colorwash

75. VMAT

76. VMAT: Dose Colorwash

77. VMAT: low dose fall-off

78. Nodal RT
(SCF +/-
Axilla)
1. Direct Anterior Field
2. HighTangents
3. VMAT

79. Direct
anterior
field

80. High tangents to cover SCF

81. VMAT

88. Field
Matching
1. In 2-dimensional planning
2. Single IsocentricTechnique
3. VMAT

89. Angulation
By inferior angulation of the
tangential fields.
Half beam block technique
Blocking the supraclav field’s
inferior half, eliminating its
divergence inferiorly .
Hanging block technique
Superior edge of tangential beam
made vertical by vertical
hanging block.

90. Single Isocentric planning: Beam Arrangement

92. Single Isocentric planning: Dose colorwash

93. Boost
Planning
1. Electrons
2. 3D-CRT usingTangents/Multiple oblique fields
3. Brachytherapy

94. Interstitial BrachytherapyElectrons
Photons

96. Boost by tangents

97. Boost by 3D-CRT

98. Boost by brachytherapy

99. Case  48/F Postmenopausal
 C/O Lump in Right Breast x 6 months
 Baseline exam : cT2N0M0 , Upper outer quadrant
lesion
 Bx : IDC, ER/PR+ , Her2/neu equivocal
 Metastatic workup negative
 UnderwentWLE with ALND
 HPE: 2.8 cm tumor with negative margins, LNs –
0/11
 Received Adjuvant chemo, 4 cycles CEF and 4 cycles
Doce q3wkly
 Planned for Adj RT 42.50 Gy/16#/3 wks toWhole
Breast f/b boost to tumor bed

110. PTV Coverage:
D95 : 40.50 Gy (95.4% of prescribed dose)
Dmax : 46.9 Gy (109%)
OARs Tolerable Dose Achieved
Esophagus Dmean < 32 Gy
V30 < 60 %
Dmean = 4.23 Gy
V30 = 0%
Spinal Cord Dmax < 50 Gy Dmax = 2.91 Gy
Right Lung Dmean < 20 Gy
V20 < 30%
Dmean = 13.00 Gy
V20 = 29.4%
Left Lung Dmean < 20 Gy Dmean = 0.6 Gy
C/L Breast Dmean < 3 Gy Dmean = 1.5 Gy
Heart Dmean < 26 Gy
V30<46%
Dm = 4.41 Gy
V30 = 0%