ESTRO 36 Abstract Book

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S642 ESTRO 36
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Purpose or Objective
The risk of breast failure after breast-conserving
treatment is two-fold higher in invasive carcinoma with
positive surgical margins than in free margins, (between
12 and 34% at ten years) (1). A new resection is
recommended, with risk of fair cosmetic result, or
mastectomy. With close margin total dose should be
higher to avoid local recurrence. Twenty years ago, we
started with a high dose rate (HDR) boost after whole
breast irradiation in cases with close or positive margin.
We review the long-term outcome in these high risk cases
Material and Methods
Between 12.1996 and 12.2011, 248 patients were
included, with a median age of 55 (22-90). Mean FU 127
months. By T stage 179 T1, 62 T2 and 6 T3. By margin
status, 120 was positive, 76 close until 2mm, 52 close
>2mm and <5mm. All of them were treated with whole
breast irradiation (WBI) 50Gy plus HDR boost with 3
fractions of 4.4Gy to 85% isodose in two days, with rigid
needles. The contour of CTV was decided by clinical
assessment, no CT planning was used. Chemotherapy was
used in 52%, and hormonal treatment in 76%. Survival was
calculated by Kaplan Meyer method.
Results
In the whole population, actuarial breast failure at 10 and
15 years was 6.5% and 11.6%. With positive margin: 6.8%
and 14.8%, with close margin ≤2mm: 9.8% and 9.8%, with
margin >2mm <5mm, 2% and 2%. By age, in 90 patients
aged 50 or younger, was 11.9% and 17.8%, between 51-70,
3.8% and 8.2%, and no failures over 70. In young women
under 50 with positive margin, breast recurrence was
13.1% and 24% at 10 and 15 years. By T stage, no
differences between T1 and T2, no failures in T3. No
differences if margin was due to invasive carcinoma or
DCIS, in G3, or depending on hormonal receptors. Fibrosis
or induration were registered in 26.7%, breast edema
6.5%, volume reduction 6.5%, telangiectasia 3.4%,
hyperpigmentation 2.1%. Cosmetic outcome was
excellent/good in 85.8%.
Conclusion
Long-term breast control of patients with positive or close
surgical margin using WBI plus a HDR boost is similar to
that achieved with free margins in the EORTC 22881-10882
trial, in all groups of age, but in young women with
positive margin where a new resection is recommended.
This approach is useful to avoid a second intervention, in
women over 50 with positive surgical margin, or with close
margins in all ages.
(1) Guinot JL, et al. Breast-conservative surgery with close
or positive margins: can the breast be preserved with high-
dose-rate brachytherapy boost? Int J Radiat Oncol Biol
Phys 2007; 68:1381-87
EP-1185 Post-operative Irradiation after Nipple-
Sparing or Skin-Sparing Mastectomy: An International
Survey
G.N. Marta1,2, P. Poortmans3, R.A. Audisio4, R. Freitas
Junior5, A.C. De Barros6, J.R. Filassi7, S.M. DeSnyder8, S.
Meterissian9, T.A. Buchholz 10 , T. Hijal11
1 Hospital Sírio-Libanês, Radiation Oncology, São Paulo,
Brazil
2 Instituto do Câncer do Estado de São Paulo ICESP -
Faculdade de Medicina da Universidade de São Paulo,
Radiation Oncology, Sao Paulo, Brazil
3 Radboud university medical center, Radiation Oncology,
Nijmegen, The Netherlands
4 University of Liverpool, Surgical Oncology, Liverpool,
United Kingdom
5 Universidade Federal de Goias, Surgery, Goias, Brazil
6 Hospital Sírio-Libanês, Surgery, Sao Paulo, Brazil
7 Faculdade de Medicina da Universidade de São Paulo
FMUSP, Breast Surgery Division, Sao Paulo, Brazil
8 The University of Texas MD Anderson Cancer Center,
Surgical Oncology, Houston, USA
9McGill University Health Centre, Surgery, Montreal,
Canada
10The University of Texas MD Anderson Cancer Center,
Radiation Oncology, Houston, USA
11McGill University Health Centre, Radiation Oncology,
Montreal, Canada
Purpose or Objective
Skin sparing mastectomy (SSM) and nipple-sparing
mastectomy (NSM) have entered routine surgical practice
for breast cancer, though their oncologic safety has not
been established in randomized controlled trials. The aim
of this study was to evaluate breast surgeons’ opinions
concerning the indications of post-operative radiation
after SSM and NSM.
Material and Methods
Breast surgeons from North America, South America and
Europe were invited to contribute in this study. A 22-
question survey was mailed to participating breast
surgeons to evaluate their opinions. the indications of
post-operative radiation after SSM and NSM.
Results
A total of 252 breast surgeons answered the questionnaire.
Most of them had at least 10 years of post-residency
practice. The majority of breast surgeons affirmed that
post-operative radiation should be performed in early-
stage (stages I and II) breast cancer for patients
who present with risk factors for relapse after SSM and
NSM (85.0% and 81.0%, respectively). They considered
age, lymph node involvement, tumor size, extracapsular
extension, involved surgical margins, lymphovascular
invasion, triple negative receptor status and multicentric
tumor as major risk factors. Considering tumor size, lymph
node involvement and age as recurrence risk factors, the
most-often suggested cut-off thresholds of those features
were 5 cm, > 3 lymph nodes and 40 years old, respectively.
Considering that after SSM and NSM, residual breast tissue
can be left behind, the residual tissue considered as
acceptable in the context of an oncologic surgery were 1
to 5 mm and 6 to 10 mm for 55% and 21% of the responders,
respectively. There is no consensus for the necessity of
evaluating residual breast tissue through breast imaging.
Conclusion
Although the indications of post-
operative radiation therapy after SSM and NSM are not well
defined, all standard relapse risk factors were considered
as important, by surgeons, with regards to referring for
post-operative radiation therapy.
EP-1186 Real-time intrafraction motion in breast
radiotherapy using an optical surface scanner
D. Reitz1, S. Schönecker1, P. Freislederer1, M. Pazos1, M.
Niyazi1, U. Ganswindt1, C. Belka1, S. Corradini1
1LMU University of Munich, Radiation Oncology, Munich,
Germany
Purpose or Objective
Intrafraction motion is of special interest in modern breast
cancer radiotherapy. Respiratory motion during intensity-
modulated radiotherapy (IMRT) can cause problems in
inadequate planning target margins or IMRT delivery. To
date, only few data exist on real-time measured
intrafraction motion in breast cancer patients. Continuous
surface imaging using visible light offers the possibility to
monitor patients’ movements in 3D-space without any
additional radiation exposure.
Material and Methods
We observed thirty-one patients during 629 fractions that
underwent postoperative radiotherapy following breast
conserving surgery or mastectomy. During each treatment
session the motion of the patient was continuously
measured using the Catalyst TM optical surface scanner (C-