ESTRO 36 Abstract Book

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S636 ESTRO 36
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Purpose or Objective
To evaluate acute skin toxicity and cosmesis in DCIS
patients enrolled in a phase II trial of hypofractionated
breast irradiation using VMAT.
Material and Methods
Patients treated for DCIS with breast-conserving surgery
were eligible for a phase II trial of hypofractionated breast
irradiation. All DCIS patients underwent VMAT technique
to irradiate the whole breast with a total dose of 40.5 Gy
delivered in 15 fractions over 3 weeks, without tumor bed
boost. Acute skin toxicities were recorded according to
RTOG scoring criteria, and late skin toxicities according to
CTCAE v4.0. Cosmetic outcomes were assessed as
excellent/good or fair/poor according to the Harvard
scale.
Results
From May 2013 to March 2016, 123 DCIS patients accrued.
Median age was 56 year (range 30-82 years). The median
follow up was 18 months (range 6-63). Most of the tumors
were moderately differentiated (51 %) with a no comedo
subtype with necrosis DCIS histology (73 %). Sentinel node
biopsy was performed in 57 patients (46,3 %). Concomitant
hormonal therapy was administered in 16 %. At the end of
RT treatment skin toxicity profile was G1 in 56% of the
patients, G2 in 14%, no patients presented G3 toxicity. At
six months of follow up skin toxicity was G1 in 25% of
patients, no G2-G3 cases; cosmetic outcome was
good/excellent in 92% of patients. At one year skin toxicity
was G1 in 24% of patients; no G2-G3 toxicity was recorded;
cosmetic outcome was good/excellent in 94% of patients.
After an early evaluation of clinical outcomes we have
found 3 cases of local relapse.
Conclusion
These results evidence that hypofractionated
radiotherapy using VMAT is a safe option for DCIS. A longer
follow up is needed to assess clinical outcomes and late
toxicity.
EP-1171 Thermography and association to high-grade
radiation dermatitis: a prospective trial on 64 patients.
N. Leduc1, V. Atallah2 , A. Petit1, S. Belhomme1, P.
Sargos1, V. Vinh-Hung3
1 Institut Bergonié, Radiation Oncology, Bordeaux, France
2 University Hospital of Bordeaux, Radiation Oncology,
Bordeaux, France
3 University Hospital of Martinique, Radiation Oncology,
Fort-de-France, France
Purpose or Objective
Thermography has been successfully used for non-invasive
imaging of various diseases. Radiation-induced dermatitis
characterizes by an inflammatory state and sensation of
heat. We designed a prospective, observational, single-
center study to acquire data about the bi-dimensional
evolution of temperature in the treated breast during the
course of radiotherapy, seek possible association with the
occurrence of dermatitis and eventually inquire about the
predictive value of temperature increase over the future
occurrence of radiation dermatitis.
Material and Methods
All consecutive patients treated for localized breast
cancer at the University Hospital of Martinique between
May and September 2016 were eligible for inclusion.
Included patients were examined weekly by trained
investigators for the occurrence of radiation dermatitis. A
high-resolution frontal image of torso was taken every
week. Treated and contralateral areas were compared.
Results
64 patients were included. All demonstrated an increase
in local temperature over the course of treatment. The
occurrence of high grade radiation-induced dermatitis was
significantly associated to a higher increase of local
average temperature (1.88 vs. 1.15 °C, p < 0.0001).
Preliminary results analyzing the predictive value of prior
temperature elevation over subsequent occurrence of
high-grade radiation dermatitis showed highest sensitivity
and specificity of respectively 75% and 69% with a
temperature threshold of 1.4°C. Figure 1 demonstrates
typical thermal images of torso at 0 and 50 Gy.
Temperature is plotted in °C.
Conclusion
This study demonstrated the feasibility of capturing local
temperature elevation over the course of adjuvant
radiotherapy for breast cancer. Maximal and average local
temperature increased for all patients, confirming the
intensity of inflammatory phenomena linked to
irradiation. Patients suffering from high-grade radiation-
induced dermatitis radiated noticeably more heat.
Furthermore, they started doing so before the occurrence
of clinical signs of dermatitis. As such, thermography
showed promising results as a predictive tool for the
occurrence of acute skin toxicity.
EP-1172 Post-mastectomy radiotherapy with patient-
tailored bolus using 3D printing for left breast cancer
K. Yang1, Y. Chung1, W. Park1, S.G. Ju 1, S.J. Huh1, D.H.
Choi1, H. Cha1, J.Y. Park1, C.H. Na1
1Samsung Medical Center, Radiation Oncology, seoul,
Korea Republic of
Purpose or Objective
Radiation exposure to the heart during radiotherapy for
left breast cancer patients has a chance to increase the
risk of cardiovascular disease. Also, radiation pneumonitis
and decreased lung function associated with thoracic
radiotherapy have been reported. The purpose of this
study is to reduce heart and ipsilateral lung doses using an
optimized chest wall electron beam therapy with patient-
tailored bolus (PTB) using 3D printing technology for left
breast cancer patients after mastectomy.
Material and Methods
Five patients with left breast cancer underwent computed
tomography (CT) simulation for irradiation of left chest
wall and supraclavicular fossa after mastectomy. We
designed a virtual bolus on the chest wall to compensate
the surface irregularities on CT images and developed a
plan for chest wall electron beam therapy. Also, a rival
plan for conventional tangential technique was done on
the same CT. For both plans, supraclavicular field was
planned using photon beam. For planning, virtual bolus
was overridden by a density of material which would be
used to make PTB with 3D printer. Dosimetric comparisons
for target and organs at risk such as heart and ipsilateral
lung were performed between the 3D PTB applied electron
beam plan and tangential plan. Wilcoxon signed-rank test
was used for statistical analysis.
Results
For cardiac dose, PTB applied electron plan showed lower
D mean, Dmax. V5Gy and V30Gy than tangential plan (p=0.080,
0.043, 0.686 and 0.068, respectively). For ipsilateral lung,