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Figure 2 screenshots of the app that will be released to
our pilot group of patients in November 2016.
Conclusion
We have developed Opal, a smartphone app and web
portal, for oncology patients at our comprehensive cancer
centre. Opal provides patients with access to their PHI,
appointment schedules, waiting room management,
relevant just-in-time educational material and patient-
reported outcomes
questionnaires.
Development is currently in the closed beta phase with
testing provided by volunteers with fake electronic health
records. We will release the app to a pilot group of
radiation oncology patients in November 20 17, followed
by general release to all radiation oncology patients in
early 2017. Release of the app to all oncology patients is
planned for the spring of 2017.
EP-1731 What can reveal onsite end-to-end audit? The
experience of national dosimetry audit group
I. Koniarova
1
, I. Horakova
1
, V. Dufek
1
1
National Radiation Protection Institute, Department of
Radiotherapy and X-ray Laboratory, Praha, Czech
Republic
Purpose or Objective
National Radiation Protection Institute performs on-site
audits in the Czech Republic. In total, 53 on-site end-to-
end audits for prostate and 16 for H&N/brain radiotherapy
were performed. Prostate case was verified in the national
run for all centres using IMRT in 2013 and repeated for
majority of centres with upgrade/installation of new
linacs in 2014-2016. There was a pilot run with head
phantom in 2016. Majority of results were within
tolerances. All results were analysed to describe the most
interesting findings and the weakest points.
Material and Methods
Absorbed doses with ionisation chambers and plane doses
with EBT3 films were measured in the pelvic or head
phantom. Following aspects can be assessed: unit
calibration, TPS model accuracy for reference field, MLC
accuracy, CT numbers to RED conversion in terms of its
influence to dose, phantom geometrical offset at the
couch, optimisation constraints, radiobiological plan
parameters calculated from DVHs. Anthropomorphic
phantoms (pelvic and head) with benchmark PTVs and
OARs were used. Three sets of audit results were analysed:
prostate audit national run, repeated prostate audit,
H&N/brain audit pilot run. Methodology is applicable to C-
arm linacs, Tomotherapy, Leksell Gamma Knife, and
proton beams. H&N/brain audit is more complex than
prostate one, and chamber cavity volume is taken into
account more carefully which enables to keep tight
tolerances.
Results
Centres which participated in the previous run did not
perform better than centres which participated for the
first time in prostate audit. However, results were
sufficient in all cases. There was not significant
improvement in results with installations of new linac and
TPS. Better MLC performance was observed but CT
number to RED was still the problematic
point. Differences in planning approaches can be seen.
Weakest point for the head audit was the phantom
positioning on the couch (despite using IGRT). Tolerances
for film evaluation depend on the dose gradient in the
direction perpendicular to the film plane. We use 95% or
90% (4%/3mm) for gamma index for prostate/ H&N or brain
plans respectively. In future, pseudo-3D gamma analysis
will be implemented.
Conclusion
It is not straighforward to identify the causes of
deviations, especially when they lie within tolerance
limits. Nevertheless, it is possible to identify systematic
errors which might be vendor dependent, user dependent,
or TPS dependent. These can help to optimise the national
quality standard in radiotherapy. We recommend not to
use rigid marks on phantom but let the centre apply their
own fixation and positioning procedure. We recommend to
include CT scanning process and identical „patient“ set-
up procedure employing RTTs. When designing audit
methodology, it is necessary to analyze pilot run results
first and then optimise procedure dependent tolerances.
This work has been supported by the project No.
TB04SUJB001 and by the Ministry of Interior of the Czech
Republic, project No. MV-25972-53/OBVV-2010.
EP-1732 Treatment planning of dose escalation for anal
cancer in the PLATO trial
N.L. Abbott
1
, D. Christophides
2
, M. Robinson
3
, J.
Copeland
4
, R. Adams
5
, M. Harrison
6
, M. Hawkins
3
, R.
Muirhead
3
, D. Sebag-Montefiore
2
1
Velindre Cancer Centre, National Radiotherapy Trials
QA group, Cardiff, United Kingdom
2
University of Leeds, Leeds Cancer Centre- St James
University Hospital & Leeds CRUK Centre, Leeds, United
Kingdom
3
University of Oxford, CRUK/MRC Oxford Institute for
Radiation Oncology, Oxford, United Kingdom
4
University of Leeds, Clinical Trials Research Unit,
Leeds, United Kingdom
5
Velindre Cancer Centre, Cardiff, United Kingdom
6
The Hillingdon Hospital NHS Foundation Trust,
Uxbridge, United Kingdom
Purpose or Objective
P
ersona
L
ising
A
nal cancer radiotherapy
d
O
se
(PLATO)
is
a complex integrated protocol, including ACT5 for high
risk patients.
ACT5 compares standard and dose escalated radiotherapy.
As part of trial development a planning study was carried
out by lead centres to determine the impact of dose
escalation on OAR sparing. Following this study a
benchmark planning case was selected and sent to fifteen
UK centres as part of the radiotherapy quality assurance
programme (RT QA), co-ordinated by the national QA
group. These centres will randomsie the first 60 patients
in a pilot phase of the trial.
We report the results of the planning study and benchmark
planning case with respect to achievable OAR sparing with
ACT5
dose
escalation.