755 / 1082
S739
ESTRO 36 2017
_______________________________________________________________________________________________
Our data support that L5%P (alone or in association with
other drugs) may be an effective and safe approach for
FNP in cancer patients.
EP-1397 Dose painting guided by diffusion-weighted
MRI applied to recurrent glioblastoma: a phase I
protocol
M. Iori
1
, M. Galeandro
2
, A. Botti
1
, R. Sghedoni
1
, P.
Ciammella
2
, M. Orlandi
1
, M. Napoli
3
, S. Tanzi
4
, R.
Pascarella
3
, S. Cavuto
5
, A. Pisanello
6
, M. Russo
6
, E.
Cagni
1
, D.E. Chiari
7
, M. Campioli
8
, C. Iotti
2
1
Arcispedale S. Maria Nuova - IRCCS, Medical Physics
Unit, Reggio Emilia, Italy
2
Arcispedale S. Maria Nuova - IRCCS, Radiation Oncology
Unit, Reggio Emilia, Italy
3
Arcispedale S. Maria Nuova - IRCCS, Neuroradiology
Unit, Reggio Emilia, Italy
4
Arcispedale S. Maria Nuova - IRCCS, Palliative Care
Unit, Reggio Emilia, Italy
5
Arcispedale S. Maria Nuova - IRCCS, Infrastructure
Research and Statistic, Reggio Emilia, Italy
6
Arcispedale S. Maria Nuova - IRCCS, Neurology Unit,
Reggio Emilia, Italy
7
UNITN, Dipartimento di Fisica, Trento, Italy
8
UNIMORE, Dipartimento di Scienze e Metodi
dell’Ingegneria, Reggio Emilia, Italy
Purpose or Objective
Standard treatment for glioblastoma (GBM) is surgery,
followed by radio- & chemo-therapy. However, disease
recurs in almost all patients and re-irradiation is an option
to be considered. Although the topic of re-irradiation is
generally controversial because of the toxicity risk,
literature provides consistent data supporting both the
feasibility and the survival-strengthening capability of
radiation, compared to supportive care only. In the
present study, voxel-based re-irradiations guided by
magnetic resonance imaging (MRI) were simulated and
planned with apparent diffusion coefficient (ADC) used as
biomarker for tumor cellularity.
Material and Methods
The relapse areas of 6 selected GBM patients treated with
STUPP protocol were monitored with MRI. The ADC
patterns, considered in the literature as a surrogate
biomarker of cellularity was analyzed and chosen to define
a signal-to-dose transfer function. This decision, coupled
with our clinical data in re-treating GBM with moderate
hypo-fractionation regime (Ciammella et al, Clin Neurol
Neurosurg, 2013, 115: 1609-14), have formed the basis of
a phase I study undertaken on 12 GBM relapse patients,
simulated with multi-parametric MRI and re-treated with
a dose-painted hypo-fractionated regime. The study
foresees dose levels of 30-50Gy/5fr with a cumulative
BED
10
>120Gy in an attempt to achieve some changes in the
recurrence pattern, without causing excessive radiation
necrosis (<12 Gy/fr) inside the irradiated area and
respecting the previously irradiated healthy tissue (EQD
2
<
100Gy). To realise the ADC data extraction and DPBN
(Dose Painting By Numbers) planning procedure with
RapidArc technique, home-made MATLAB software and
automatic scripting procedure on a commercial treatment
planning system (TPS) were realised. Nine target sub-
volumes were used for the volume-based TPS plan
optimisation. Phantom (PTW, Octavius 4D) and portal
dosimetry (EPID) based on g-index (2%, 2mm) were applied
for the pre-treatment plan evaluation.
Results
Considering follow-up data that correlates patient
outcomes with histogram changes in the tumour
recurrence ADC values of the 6 relapsed patients, a double
threshold transfer function was defined. The first patient
was enrolled in the study and treated. To a first control to
three months after treatment, the first patient has not
had acute toxicity, has a performance status of 100%, and
has a radiological picture of stable disease albeit
associated with signs of pseudo-progression. The pre-
clinical check of the delivered treatment, verified with
portal and phantom dosimetry, has provided a minimum
g-index of 90.7%. The total beam-on time with 4 non-
coplanar 6MV FFF arcs was less than 5 min.
Conclusion
The phase I protocol, approved by Ethical Committee, has
enrolled its first patient. Data on planning, dosimetric and
patient follow-up aspects will be presented and discussed.
EP-1398 Application of radiosurgery in treatment of
oligometastases
T. Chebotarova
1
, N. Spizhenko
1
, N. Lisovzka
1
, O. Yarmak
1
1
Cyber Clinic of Spizhenko, Radiation therapy,
Kapitanivka -Kyiv region, Ukraine
Purpose or Objective
Development of genetic researches in the field of oncology
found out proofs of genomic instability in solid tumors
which results in their clonal heterogeneity.
Oligometastatic disease considered as an intermediate
biological state with limited ability of tumor to promote
numerous metastases. In this transition stage of growth
tumor could gave oligometastatic clones expressed with
single metastatic lesions. Now it’s known, that the cells of
oligometastatic tumors expressed specific microRNAs able
to block tumor-promoting genes, and as a result make the
spread of tumors slower. We are focusing on the group
patients with metastatic lesion aiming to detect clinical
application for local ablative radiosurgery treatment.
Material and Methods
The results of treatment of 335 patients with metastases
of brain, lung, liver, renal and epinephrine were analyzed.
The localization of primary tumors in this group of patients
was in breast, lung, colorectal and kidney. Performance
status of patients was 0-1 according ECOG-scale. All
patients have previously radically treated primary tumor
and no more than 3-4 distant metastatic lesion by the
moment of treatment. Patients receive radiosurgery or
hypofractined irradiation in a single dose 6-20 Gy and total
summary dose 20-60 Gy by using CyberKhife system.
Results
In 31 patients with distant metastases in brain, lung, liver,
renal and epinephrine after local ablative radiosurgery we
registered full tumor regression during 2-6 years. The
existence of this group of patients clinically confirms
molecular differences between higher and low metastatic
potential tumors. That is why previously shown genetic
features of oligometastatic tumors change our ideas about
possibilities of active local treatment in cases of
metastatic disease.
Conclusion
Thus, our observations clinically confirm the existence of
group of patients with oligometastatic tumor disease
caused by specific genomic changes in tumor cells. In such
cases, local ablative radiosurgery with precision and high
doses of radiation could be curative.
EP-1399 Rotary-Dual Total Skin Electron Beam Therapy
as palliative treatment for mycosis fungoides
A. Jodda
1
, M. Pawlaczyk
2
, M. Fundowicz
3
, T. Piotrowski
4
1
Greater Poland Cancer Centre, Medical Physics, Poznan,
Poland
2
Poznan University of Medical Sciences, Skin Diseases
Prevention, Poznan, Poland
3
Greater Poland Cancer Centre, Radiotherapy, Poznan,
Poland
4
Poznan University of Medical Sciences, Electroradiology,
Poznan, Poland
Purpose or Objective
To retrospectively assess the efficacy and toxicity of a
total skin electron beam therapy (TSEBT) in patients with
primary cutaneous T-cell lymphoma at various stages of
development.