ESTRO 36 Abstract Book

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S160 ESTRO 36 2017
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currently not any deformable registration algorithms
which have shown performance in sigmoid and bowel
which is sufficent for dose accumulation. In conclusion,
DVH addition is currently recommended by the ICRU 89
report for dose summation in brachytherapy, and provides
in most scenarios a good accuracy for assessment of total
dose in targets and in organs such as bladder and rectum.
Dose summation in highly mobile organs such as sigmoid
and bowel is currently related with significant
uncertainties, and there could be potential to improve this
with appropriate DIR algorithms.
SP-0312 Imaging and fusion techniques for focal
brachytherapy
L. Beaulieu1
1 Laval University - Faculty of Science and Engineering,
Université laval Cancer Research Centre, Québec City,
Canada
Over the last decade, numerous technological
developments have made brachytherapy one of the most
precise needle-based procedures on the market. The
cornerstone of interstitial brachytherapy for many years
now has clearly been real-time ultrasound (US) image-
guidance and more recently real-time 3DUS image-
guidance. From whole gland prostate cancer treatments
to focal boosts and now focal therapy, brachytherapy is
head of the curve of any other prostate focal therapy
modality at this time in terms of precision and accuracy.
However, current standard US-guidance is not sufficient
for focal therapy; our real-time image-guidance technique
needs to be supplemented with more information. This
presentation will look at the role of multi-parametric MRI
in prostate focal therapy as well as US-augmented with
MRI for real-time guidance. This brings the notion of
augmented reality as well as the challenge of image fusion
among two very different imaging modalities and image
sets also taken under very different conditions. We will
also discuss the topic of merging tissue information (e.g.
biopsy) with imaging data to provide a complete cancer
burden maps for targeting purposes. Finally, we will
provide a forward-looking view of real-time multi-
parametric 3DUS guidance and targeting for such
procedures.
Proffered Papers: Breast and gynaecology
OC-0313 What is the effect of axillary treatment on
patient reported outcomes in breast cancer patients?
M.L. Gregorowitsch1, H.M. Verkooijen1, N. Fuhler1, D.A.
Young Afat1, A.N.T. Kotte1, M. Vulpen van1, C.H. Gils
van2, D.H. Bongard van den1
1 University Medical Center, Radiation Oncology, Utrecht,
The Netherlands
2 Julius Center for Health Sciences and Primary Care-
University Medical Center, Epidemiology, Utrecht, The
Netherlands
Purpose or Objective
In breast cancer patients with limited (sentinel) lymph
node involvement, axillary lymph node dissection (ALND)
is increasingly being replaced by axillary radiotherapy.
Since ALND is associated with a high risk of upper-body
morbidity, axillary radiotherapy might be favorable in
patients with limited lymph node involvement. However
radiation-induced morbidity can also influence quality of
life, the extent of which may depend on the irradiated
volumes. We compared patient reported outcome
measures (PROMs) of breast cancer patients at the start
adjuvant radiotherapy, during and after radiotherapy
according to the extent of axillary treatment.
Material and Methods
This study was conducted within the Dutch UMBRELLA
cohort (i.e. prospective observational cohort including
breast cancer patients indicated to receive adjuvant
radiotherapy at the department of Radiation Oncology at
the University Medical Centre Utrecht). All participants
consented to collection of clinical data and patient
reported outcomes (PROMs). Arm function and Quality of
Life (QoL) were measured by EORTC QLQ-C30 and BR23.
We first compared differences in mean PROM scores
between patients who underwent ALND and those who did
not by two sample t-test. In a second step, we estimated
the effect of extent of axillary radiotherapy on PROM
scores in patients stratified on ALND, and used analyses of
variance (ANOVA) to test for differences. Finally, we
compared patients who underwent ALND and local RT with
non-ALND patients treated with axillary RT to estimate the
differences between axillary RT and ALND.
Results
Between October 2013 and December 2015, 521 patients
were enrolled. In total 75% (n=390) of the patients were
treated with local radiotherapy on the breast/chest wall
(local RT), 10% (n=53) received additional axillary
radiotherapy on level I and II (local RT + level I-II) and 15%
(n=78) of the patients received local radiotherapy with
axillary irradiation including levels III and IV (local RT +
level I-IV) (Table 1). ALND (n=84) was performed in 10%
(n=40) of the patients in the local RT group and in 56%
(n=44) of the locoregional RT group (Table 1). Patients in
the ALND group reported significantly lower arm function
compared to the non-ALND group (Figure 1A-B). For
patients who underwent ALND and local RT, arm symptoms
were significant worse at baseline and 3 months compared
to non-ALND patients who received local RT and axillary
(level I-II or level I-IV) irradiation (MD -15.2, p=0.00 and -
13.4, p=0.00) (Figure 1C). Overall QoL scores were similar.