There is no data available that demonstrate that radiation therapy needs to be delivered to the whole breast. The only contemporary studies available applied extensive microscopic evaluation of both mastectomy and quadrantectomy specimens and all three of these studies focused on the distance of DCIS beyond the primary lesion. One looked at DCIS extension beyond the primary IDC and one study from primary DCIS lesions. All presented evidence suggesting that the extension of malignant cells is limited to less than 1cm from the primary lesions, except for younger patients.
For correct delivery of a boost, precise demarcation of the excision cavity is mandatory; it has been estimated that the externally delivered boost misses the target volume in 24-88% of cases.
At 5 years, APBI patients continued to experience a higher proportion of adverse cosmesis (32.8% v 13.4%; absolute difference, 19.4%; 95% CI, 10.4 to 27.9; P.001).
Accelerated partial breast irradiation
ACCELERATED PARTIAL BREAST
MODERATOR:- DR PUNITA LAL
5.Review of literature
Outcomes and patterns of failure
Toxicities and challenges
Comparison of different techniques
6. Ongoing trials
7. Pre-op APBI !!!!
Based on 6 RCT & meta-analyses it was shown
that RT is an integral component of breast
conservation therapy and is the std. of care in
early breast cancer
15% to 30% of patients who undergo
lumpectomy do not receive radiation therapy
Hershman Dlet al. J Natl Cancer Inst 2008;100:199–206.
Pawlik Tmet al. J Am Coll Surg 2004;199:479–92.
Commitment to the 6- 7 week course of
adjuvant conventional RT
Distance from the radiation therapy facility
Lack of transportation
Lack of social support structure
Poor ambulatory status of the patient
Fear of radiation treatment
SO THE QUESTION ARISES THAT
‘ can similar rates of local control be achieved with
radiation therapy delivered only to the area at highest
risk for recurrence?’If so, radiation could be delivered
in a significantly shortened period
Veronesi U, et al. NEJM 2002;347:1227–32
Majority of local recurrences (LRs) occur in proximity to the tumour
Less than 20% of LRs appear ‘‘elsewhere” in the breast the absolute
number of such failures is very low.
< 1% per yr . & similar to the recurrence of contra-lateral second
primary breast cancer.
30,000 pts have been treated outside the clinical
trial in past few years despite encouraged use of
APBI in clinical trial only.
Ongoing RCT will be published in next 3-5 yrs.
Give recommendations on patient selection criteria
for the use of APBI outside the context of
prospective clinical trials
CLINICAL RESULTS OF APBI USING
SUBOPTIMAL PATIENT SELECTION
Results were poor, with high LR rates exceeding 1% per year
Polgar et al,Radiotherapy and Oncology 94 (2010) 264–273
Shah et al. Brachytherapy 12(2013) 267-77
Direct visualization of the lumpectomy cavity/clips
Free hand method
After catheter placement , wound closure and
Closed cavity implant
After the final pathology information to guide
appropriate patient selection.
Local anaesthesia given 15-30 min before the
Simulator /CT based
Appropriate number of catheters
Number of catheter planes
Optimal direction of placement.
Lumpectomy cavity plus a 2-cm margin
Near chest wall and skin -1 to 1.5 cm
HDR-34 Gy/10# bid in 5 days
LDR- 45 Gy @ 50 cGy/hr over 4.5 days
Arthur et al. IJROBP 2003 vol 56, 681-9
Free hand technique
Template to ensure even needle spacing
Under image guidance using
Combination of modalities
DESIGN OF THE IMPLANT GEOMETRY
Needles are implanted parallel and equidistance from
each other (Paris system).
In most cases inserted in a mediolateral direction.
In very medially or laterally located tumor sites, needles
should be implanted in a craniocaudal direction to
enable separate target area from skin points.
In some rare cases, the upper outer quadrant has to be
implanted with needles orientated in a 45° angle to
avoid overlap of source positions and skin
2 planes of needles are usually needed
to cover the PTV.
Single plane< 12 mm.
Three planes are required in a large breast where
the targeted breast tissue between pectoral fascia
and skin is thicker than 30 mm.
Five to nine needles spaced 15–20 mm are usually
REDUCTION IN SKIN DOSE
Skin to source measuring bridge is used.
If the superficial needles are too close to the skin, the
templates are moved towards each other so that the
overlying skin moves up and away from the needles.
If this is not sufficient, templates with a smaller spacing
between the needles are used, resulting in compression
of the breast tissue and upward movement of the skin
Some gauze is disposed between the templates and the
skin of the thoracic wall at both sides of the implant to
avoid skin necrosis secondary to continuous pressure of
Better control and tailoring of radiation-dose
delivery to variations in lumpectomy cavity, shape,
or location within the breast.
Limits toxicity to healthy tissue while delivering the
maximum dose to at-risk tissue.
Critical structures can be avoided by differential
loading of the catheters
Considerable training and experience
Appearance and patient acceptance of multiple
catheter implants in the breast
high skin dose: great care is required to ensure
adequate source-to-skin distance in patients
treated with brachytherapy
Therefore, may not be a viable treatment option for
patients with superficial tumors or small breasts
Njeh et al. Radiation Oncology 2010, 5:90
Double-lumen catheter (15 cm length and 6 mm in
Inflation channel:- saline solution mixed with a small
amount of contrast material to aid visualization.
Source channel:- for passage of an Ir-192 high dose
rate (HDR) brachytherapy source.
Source channel runs centrally through the length of the
after lumpectomy, the catheter is placed in the breast cavity either during
the lumpectomy procedure or later through a closed technique
balloon is inflated with 35 to 70 mL of saline mixed with a small amount
of contrast material, depending on the size of the lumpectomy cavity
CT imaging to assess the adequate placement of the device
An Ir-192 radioactive source, connected to a computer-controlled HDR
remote after-loader, is inserted through the catheter into the balloon to
deliver the prescription radiation dose
QUALITY OF THE IMPLANT
Ballon Conformance: assessed by quantifying the
volume of the PTV that is filled by air or seroma
Less than 10% of the PTV should be composed of
fluid or air.
Minimum balloon-to-skin distance: for good
5-7 mm is required
Close to the skin
Essential for adequate dosimetry.
A non-symmetrical implant can result in dose
inhomogeneity in the surrounding tissues since the
MSB device contains a single, central source
channel that does not allow for shaping of the
radiation isodose curves in the direction
perpendicular to the central channel
34 Gy over 10 fractions
(3.4 Gy per fraction, twice daily )
Prescription point is 1 cm from the balloon surface
Minimum 6 hours gap
D 90> 90%
V200< 20 cc
Skin dose Max <145%
Not suitable in patients with small breast .
Tumors located in the upper-inner quadrant.
Irregular cavity .
(Requirement for skin-to-cavity distances:- not met)
More user-friendly technique for brachytherapy
•Digital touch-screen for the
Physician and Physicist
to input treatment data and
monitor treatment progress.
Specifically shielded radiation room or an HDR
afterloader unit are not required.
This reduces costs and allows for portability of the
system, which can lead to greater access for
patients particularly in more remote or rural
Can be used intraoperatively
In addition to a central lumen, the Contura balloon
has four surrounding channels to accommodate the
Additional source positions allows increased dose
flexibility compared with a single-catheter approach.
Vacuum port to remove fluid or air around the
Reduce the dose to normal tissues (chest wall and
skin) better protection of organs at risk such as the
heart and lungs.
Possible to account for asymmetric balloon implant
with respect to the central channel.
Consists of a central strut
Sorrounded by 6,8 or 10 peripheral struts
Can be differentially loaded with HDR source
Insertion done in collapsed form through an incision (LA
Then expanded to fit the cavity
CT aquired (verification and planning)
Contains six outer expandable plastic tubes to
displace the tissue
Central catheter surrounded by six additional
catheters that allow the passage of an HDR
The radiation source is not in direct contact with
the breast tissue
Non-invasive (complications of surgery like seroma
and infection can be avoided)
Technically less demanding
Treatment results with external beam may be more
uniform between radiation oncologists
Greater dose homogeneity
3.85 Gy twice daily (separated by at least 6 hours) to a total
dose of 38.5 Gy delivered within 1 week
RAPID TRIAL-RANDOMIZED TRIAL OF
ACCELERATED PARTIAL BREAST IRRADIATION
(42.5 Gy/ 16#/22
Large breasted patient :- 50 Gy/25#
Boost allowed :- 10 Gy/5# (21%)
Chemotherapy, if used, was completed before
T < 3 cm,
No BRCA1 or
CTV – tumor bed on CT , including surgical clips plus 1
cm margin inside breast tissue
PTV- CTV + 1 cm margin
Prescribed dose 38.5 Gy in 10 # bid over 5-8 days/
minimum interfraction interval 6 hours
The breast volume planning goals
0% to receive>107%
<25% (up to 35% acceptable) to receive>95%,
<50% (up to 60% acceptable) to receive >50% of
the prescription dose
Treated with 3-5 noncoplaner conformal fields
By EORTC Cosmetic Rating System.
At baseline, assessed by a trained nurse.
Assessed by two panels of three radiation oncologists
using the digital photographs on follow-up.
The treated breast was compared with size and shape,
location of the areola and nipple, appearance of the surgical
scar, presence of telangiectasia, and global cosmetic score
Median follow-up- 36 months
STANDARD OR HYPOFRACTIONATED
RADIOTHERAPY VERSUS APBI FOR BREAST
CANCER (SHARE TRIAL)
50 Gy+ 16 Gy
or 40 Gy/15#
Accurate dose delivery
Direct visualization of the tumor bed
Better protection of healthy tissues by moving them away from
the path of the radiation beam.
Eliminates the risk of geographical miss
Oxygen effect :-Rich vascularization in tissues with aerobic
metabolism, which makes them more sensitive to the action of
the radiation .
Single intraoperative application eliminates the risk of patients
not completing the prescribed course of breast radiotherapy.
Does not require a specially designed operating room
N0 difference in local recurrence
Radiotherapy toxicity was lower in the targeted intraoperative
radiotherapy group (six patients [0·5%]) than in the external beam
radiotherapy group (23 patients [2·1%]; p=0·002).
The 5-year risk for LR
was 3·3% (95% CI 2·1–
5·1) for TARGIT versus
1·3% (0·7–2·5) for EBRT
• Control console
which operates the accelerator during
radiation treatment delivery
• Modulator houses the electronic systems
of the accelerator and energizes the
accelerator to produce the electron
• Therapy module houses the accelerator
guide and control systems that generate
and deliver radiation
• 4 MeV, 6 MeV, 9 MeV and 12 MeV with
therapeutic ranges up to 4 cm
• Delivers electrons with the use of a
mobile dedicated linear accelerator
• Radiating head can be moved
by an articulated arm that can work in an
existing operating room
• It delivers electron beams at four
different nominal energies (3, 5, 7 and 9
• Beam are collimated by means of a hard
docking system, consisting of cylindrical
perspex applicators available
in different diameters (4 to 10 cm) and
angles of the head (perpendicular or
oblique 15° to 45°)
Lancet Oncol 2013; 14: 1269–77
Age > 48-
50 Gy/25# plus
21 Gy single #
Follow-up= 5.8 years
The 5-year event rate for IBRT was 4.4% in the IOERT group
and 0.4% in the EXRT group.
Significant difference in favor of WBI for different
times was also found. No differences in nodal
recurrence, systemic recurrence, overall survival
mortality rates were observed. Conclusions: APBI is
associated with higher local recurrence compared
to WBI without compromising other clinical
Conclusions: APBI is associated with higher local recurrence
compared to WBI without compromising other clinical outcomes. No
differences in nodal recurrence, systemic recurrence, overall survival
and mortality rates were observed
Low risk - APBI outside the context of a clinical trial
is an acceptable treatment option
High-risk group- APBI is considered C/I
Intermediate risk group- APBI is considered
acceptable only in the context of prospective clinical
PERMANENT BREAST SEED IMPLANT
Percutaneous insertion of radioactive seeds
(palladium-103 ) under US guidance
Use of LDR sources has the potential for improving
the therapeutic ratio
A preplan is generated with optimal seed position
and spacing to deliver the prescribed dose of 90 Gy
to cover the lumpectomy cavity with a 1.5-cm
Using a grid template 103Pd seeds are placed
according to the preplan needle and seed
NONINVASIVE IMAGE-GUIDED BREAST
Moderate compression between two mammography paddles. This
technique achieved stable position of the breast and lumpectomy
cavity for imaging and treatment.
Imaging is then performed using 30-kVp X-rays, similar to
mammography, in the immobilized position and in the treatment
Imaged-guided target delineation
The lumpectomy cavity is delineated, usually with the assistance
of radiopaque clips placed at the time of lumpectomy.
Using a target localization grid, the appropriate applicator size
and position are selected to cover the lumpectomy cavity with an
The selected tungsten alloy applicators are mounted on the
mammography paddles centered on the target.
Treatment with collimated photon emission using 192
Ir HDR brachytherapy
Treatment is then delivered using directed photons
in a parallel-opposed fashion from an 192Ir HDR
The process is then repeated along a second
intersecting orthogonal axis in a sequential manner.
The orthogonal axes are usually oriented in
craniocaudal and mediolateral directions so that
presurgical mammography can be used to further
assist and ensure appropriate target coverage
In about 5-8 years, the ongoing studies will
hopefully answer the questions related to patient
selection, long-term outcome, and toxicity of the
A modest reduction in initial treatment efficacy
cannot be justified in patients with early breast
cancer, who have an excellent prognosis with
standard BCT including WBI.
For the coming years, patients should be carefully
selected for APBI and closely followed with
accurate documentation of any occurring events.