ESTRO 36 Abstract Book

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S718 ESTRO 36
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Conclusion
Up to October 2016, 42 patients have completed the
treatment. More mature results seem to confirm the
presented preliminary ones. Our preliminary data show
the feasibility of an extremely hypofractionated schedule
with concomitant boost on the mpMRI-identified DIL. The
higher number of patients expected for the trial and a
longer follow-up are needed to confirm these results. The
secondary endpoints of the study, namely the evaluation
of late toxicity, patient free survival, overall survival,
quality of life and pattern of failure will be investigated
when more mature follow-up data will be available.
EP-1339 Feasibility and efficacy of moderately
hypofractionated radiotherapy in high risk prostate
cancer
G. Marvaso1, G. Riva 2, C. Bassi 2, C. Fodor2, D. Ciardo2, D.
Zerini2, G. Timon2, A. Surgo3, A. Maucieri 3, F. Pansini4, P.
De Marco 5, F. Cattani6, O. De Cobelli7, R. Orecchia8, B.
Jereczek-Fossa9
1 European Insitute of Oncology, radiation oncologist,
Milan, Italy
2 European Institute of Oncology, Radiotherapy, Milan,
Italy
3 IEO-University of Milan, Radiotherapy, Milan, Italy
4 European Insitute of Oncology, Medical Physics, Milan,
Italy
5 IEO- University of Milan, Medical Physics, Milan, Italy
6 European institute of Oncology, Medical Physics, Milan,
Italy
7 IEO- Univesity of Milan, Urology, Milan, Italy
8 IEO, Scientific Direction, Milan, Italy
9 IEO- University of Milan, Radiotherapy, Milan, Italy
Purpose or Objective
Prostate cancer (PCa) is the second most common male
cancer. The prognosis for patients with a diagnosis of high-
risk PCa is poor. No consensus exists on the most effective
treatment. In the last decade, hadrontherapy with carbon
ions has been considered a suitable strategy for high-risk
PCa, in terms of the dose delivery with a resulting
increased sparing of organs at risk, based on the promising
Japanese results and first Italian data from CNAO.
The aim of this retrospective study was to identify the
biochemical progression-free survival and the toxicity
profile of localized high-risk PCa patients treated with
external beam radiation therapy (EBRT). These results will
constitute a benchmark for a prospective “mixed beam”
trial: a boost with carbon ions followed by a pelvic photon
intensity modulated radiotherapy (NCT 02672449,
registered at clinicaltrials.gov).
Material and Methods
We retrospectively reviewed the data of 76 patients
treated in our Institution with photon EBRT according to
the inclusion criteria of the forthcoming “mixed beam”
trial: cT3a and/or serum prostate-specific antigen >20
ng/mL and/or Gleason score of 8-10, cN0 cM0. Toxicity,
biochemical and clinical progression-free survival were
assessed.
Results
Seventy-six patients treated between 05/2010 and
12/2014 fulfilled our criteria. Median age, initial PSA and
Gleason score were 74.9 years, 26.4 ng/mL and 8,
respectively. Prostate and vesicles or prostate and pelvis
were irradiated in 46 and 30 patients, respectively, using
intensity modulated radiation therapy. Moderate
hypofractionation was employed (Fox Chase regimen),
with a median dose of 70.2 Gy (2.7 Gy for 26 fractions). In
61 patients (80.3%) androgen deprivation therapy (ADT)
was added.
The median follow-up was 30.2 months (range 7.2-61.1
months).
Biochemical progression was observed in 22 patients
(28.9%) after a median time of 20.2 months (range: 5-
58.1) from the end of EBRT. Sixteen patients had clinical
progression, always preceded by biochemical
progression. Fifty-seven patients (75.0%) are alive with
no evidence of disease, 13 patients (17.1%) are alive with
clinically evident disease, 6 patients (7.9%) died (3 for
PCa).
No grade higher than 2 acute and late toxicity, including
urinary and rectal complications, was reported.
Conclusion
Our results suggest that a more aggressive treatment is
necessary. Local treatment intensification based on the
“mixed beam” approach combining carbon ions, with its
known radiobiological advantages, and photons might
really represent a promising strategy in the high-risk PCa
and it will be investigated with our prospective clinical
trial.
EP-1340 Comparing dosimetry and toxicity of 5-field
IMRT versus VMAT for prostate & pelvic nodal
irradiation
P. Turner1, S. Jain1, D. Mitchell2, J. Harney2, F.
Houghton2, J. McAleese2, D. Stewart2, A. Hounsell1, D.
Irvine3, G. Corey2, K. Tumelty2, K. Thompson4, J.
O'Sullivan1
1Centre for Cancer Research and Cell Biology- Queen's
University of Belfast, Advanced Radiotherapy Group,
Belfast, United Kingdom
2Northern Ireland Cancer Centre, Uro-oncology, Belfast,
United Kingdom
3Northern Ireland Cancer Centre, Radiotherapy Physics,
Belfast, United Kingdom
4Queen's University of Belfast, School of Medicine,
Belfast, United Kingdom
Purpose or Objective
There is emerging evidence supporting the use of prostate
and pelvic nodal irradiation in high-risk localised prostate
cancer. Recent evidence also suggests a role for local
prostate irradiation in metastatic prostate cancer. It is
therefore timely to assess different methods of delivering
pelvic radiotherapy from the point of view of dosimetry
and real world toxicity.
Material and Methods
The demographics, disease metrics, RTOG graded toxicity
and outcome data for 42 patients receiving prostate and
pelvic node radiotherapy in our institution over a 2 year