ESTRO 36 Abstract Book

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S630 ESTRO 36 2017
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Hence, TB delineation is sum total of information from
surgical notes, surgical clips, postoperative changes on
radiation therapy (RT) planning scans, histopathology
report and some calculated guess work.
Objective: To determine utility of preoperative CT scan
in TB delineation after BCS.
Material and Methods
This pilot study was conducted in Department of Radiation
Oncology, Max Hospital, Delhi, India, on 21 breast cancer
patients in whom prior to BCS, preoperative CT scan was
done in treatment position on a flat couch, in CT
simulator. A radio opaque fiducial was also placed at the
centre of palpable lump. After BCS & chemotherapy (if
any), RT planning CT scan was taken with similar set up as
pre-operative CT scan. Both the scans were co-registered
using non-deformable registration on Eclipse Version 10.0.
TB was contoured on RT planning CT using surgical clips
(TB1) and also on preoperative CT scan (TB2). Tumor bed
on all RT planning scans were scored for Cavity
Visualization Score (CVS). Relative shift in position of TB
on both the scans was compared in all three [lateral (RL),
cranio caudal (CC) and Antero-posterior (AP)] directions.
Results
In our patients, median age was 59 years (Range 42-71).
Median of maximum tumor size was 2.5 cm (Range 1.0-
5.0). All patients underwent BCS with oncolplastic
reconstruction. Median time between preoperative and RT
planning scan was 4.6 months. CVS 1 and 5 was observed
in 6 patients each and rest patients were having CVS 2, 3
or 4. Mean preoperative, postoperative and combined
tumor volume were 10.9cc, 10.9cc and 23.4cc
respectively. On evaluating relative positions of tumor bed
on pre-operative vs RT planning scan, mean (± SD) RL shift
was 2.8 cm (± 1.8), which was larger than for the other
directions (CC shift 1.2 cm, SD ± 0.9; AP shift 1.6 cm, SD
± 1.1). When relative shifts of TB were co-related with
tumor location, RL & CC shifts were more in outer
quadrant tumors (p=0.0005 & 0.016 respectively), while in
AP direction, p value (0.26) was not statistically
significant.
Conclusion
Preoperative CT scan in treatment position is an additional
useful tool in calculated guess work of TB delineation and
helps in improving the accuracy of target volume
delineation for TB boost.
EP-1170 Hypofractionated radiotherapy for ductal
carcinoma in situ using VMAT: acute toxicity and
cosmesis
F. De Rose1, A. Fogliata1, D. Franceschini1, C. Iftode 1,
A.M. Ascolese1, T. Comito1, L. Di Brina1, A. Tozzi1, C.
Franzese1, E. Clerici1, G.R. D'Agostino1, P. Navarria 1, F.
Lobefalo1, M. Scorsetti1
1 Istituto Clinico Humanitas, Radiotherapy and
Radiosurgery, Rozzano Milan, Italy
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. Petit 1, S. Belhomme1, P.
Sargos1, V. Vinh-Hung3
1Institut Bergonié, Radiation Oncology, Bordeaux, France
2University Hospital of Bordeaux, Radiation Oncology,
Bordeaux, France
3University 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.