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ESTRO 36
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enrollment
EP-1252 Update of Stereotactic body radiation
therapy for pancreatic adenocarcinoma: efficacy and
safety
X. Chen
1
, E. Sanchez
1
, A. Montero
1
, O. Hernando
2
, M.
Lopez
1
, J. Garcia
3
, J.M. Perez
4
, R. Ciervide
1
, J. Valero
1
,
M. Garcia-Aranda
1
, R. Alonso
2
, D. Zucca
3
, M.A. De la
Casa
3
, B. Alvarez
1
, J. Marti
3
, L. Alonso
4
, P. Fernandez-
Leton
3
, C. Rubio
1
1
Hospital Universitario HM Sanchinarro, Radiation
Oncology, Madrid, Spain
2
Hospital Universitario HM Puerta del Sur, Radiation
Oncology, Madrid, Spain
3
Hospital Universitario HM Sanchinarro, Medical Physics,
Madrid, Spain
4
Hospital Universitario HM Puerta del Sur, Medical
Physics, Madrid, Spain
Purpose or Objective
To review feasibility and single center experience with
stereotactic body radiation therapy (SBRT) in pancreatic
adenocarcinoma.
Material and Methods
Since February 2014, 15 (p) patients with a median age of
69.8 years (range 53-86) with histologically proven
adenocarcinoma of the pancreas were enrolled on this
protocol. Six p (40%) were treated with a radical intent, 5
p (33%) as a part of a neoadjuvant treatment and 4 p (27%)
under a palliative intention. Prior to radiation, at least 2
gold fiducials markers were located into the tumor guided
by endoscopic ultrasound. All the SBRT treatments
included CT or PET-CT for GTV delineation, treatment
technique was intensity-modulated radiation therapy
(IMRT) and daily image-guided radiation therapy (IGRT)
with intrafraction control of tumor motion with a Novalis
Exactrac Adaptive Gating System. Total dose: 50 Gy in 10
fractions were prescribed in 13 p (87%), 1 p was treated
with 35 Gy in 5 fractions and 1 p was treated with 40Gy in
10 fractions.
Results
With a median follow-up of 8 months (range 3 - 24
months), 2 p (13%) are alive without tumor, 4 p (26%) are
alive with tumor and 9 p (61%) have died; median overall
survival (OS) was 13.4 months (range 8.6 – 30.4 months)
and the actuarial 12 and 24 months OS was 79% and 22%
respectively. Eleven p (73%) remain locally controlled and
median time to local progression (PFS) was 11.4 (range 4.5
– 30.4 months). The actuarial PFS at 12 and 24 months
were 85% and 56% respectively. Pancreatic SBRT was well
tolerated in our cohort of patients. No grade 3 or higher
toxicity was observed. Six p (40%) developed grade 2
epigastric pain and/or grade 2 nausea/vomiting.
Conclusion
In our experience, gating SBRT for pancreatic tumor is a
feasible and well-tolerated treatment. Most patients are
free from local progression, but overall survival remains
poor. Prospective studies are needed to define the role of
SBRT for pancreatic
tumors.
EP-1253 Interobserver variability in the target
delineation of hepatocellular carcinoma.
E. Gkika
1
, S. Tandini-Lang
2
, S. Kirste
1
, P. Holzner
3
, H.P.
Neeff
3
, H.C. Rischke
4
, T. Reese
5
, F. Lohaus
6
, M.N. Duma
7
,
K. Dieckmann
8
, R. Semrau
9
, M. Stockinger
10
, D. Imhoff
11
,
N. Kremers
12
, M. Häfner
13
, N. Andratschke
2
, U. Nestle
1,14
,
A.L. Grosu
1,14
, M. Guckenberger
2
, T. Brunner
1,14
1
University Hospital Freiburg, Radiation Oncology,
Freiburg, Germany
2
University Hospital Zürich, Department of Radiation
Oncology, Zurich, Switzerland
3
University Hospital Freiburg, Department of Visceral
Surgery, Freiburg, Germany
4
University Hospital Freiburg, Department of Nuclear
Medicine, Freiburg, Germany
5
University Hospital Halle-Wittenberg, Department of
Radiation Oncology, Halle-Wittenberg, Germany
6
University Hospital Dresden, Department of Radiation
Oncology, Dresden, Germany
7
University Klinik Rechts der Isar- TU Munich,
Department of Radiation Oncology, Munich, Germany
8
General Hospital Vienna- Medical University Vienna,
Department of Radiation Oncology, Vienna, Austria
9
University Hospital of Cologne, Department of Radiation
Oncology, Cologne, Germany
10
University Hospital Mainz, Department of Radiation
Oncology, Mainz, Germany
11
University Hospital Frankfurt, Department of Radiation
Oncology, Frankfurt, Germany
12
University Hospital Freiburg, Department of Radiology,
Freiburg, Germany
13
University Hospital Heidelberg, Department of
Radiation Oncology, Heidelberg, Germany
14
German Cancer Consortium DKTK, Partner Site
Freiburg, Freiburg, Germany
Purpose or Objective
To evaluate the inter-observer variability in the gross
tumor delineation of hepatocellular carcinoma (HCC) in a
multicenter panel.
Material and Methods
The analysis was performed within the working group on
Stereotactic Radiotherapy of the German Society for
Radiation Oncology (DEGRO). A total of 9 German,
Austrian and Swiss centers with experience in upper
abdominal stereotactic body radiotherapy (SBRT)
participated in the study. Sixteen physicians (12 radiation
oncologists, 2 liver surgeons, 1 radiologist and 1 nuclear
medicine physician) were invited to delineate the gross
tumor volume (GTV) of three anonymized HCC cases. A
multiphasic CT scan from each patient was distributed to
the panel before the annual meeting. In the first case
participants were asked to delineate a peripheral well
defined HCC. The second case included a patient with a
multifocal HCC (1 conglomerate and 1 peripheral tumor).
This patient was previously treated with transarterial
chemoembolization (TACE) and the peripheral lesion was
adjacent to the previous TACE site (lipiodol uptake site).
In the last case the participants were given a CT with an
extensive HCC involvement with a portal vein thrombosis
and inhomogeneous liver parenchyma due to extensive
cirrhosis. The inter-observer agreement (IOA) was
evaluated according to Landis and Koch.
Results
The IOA for the first case was excellent (kappa: 0.85) and
for the second case moderate (kappa 0.48) for the
peripheral tumor and substantial (kappa 0.73) for the
conglomerate. In the case of the peripheral tumor the
inconsistency is most likely explained due to the necrotic
tumor cavity after TACE caudal to the viable tumor. In the
last case the IOA was fair with a kappa of 0.34 with a
significant heterogeneity concerning the borders of the
tumor and the extent of the portal vein thrombosis (PVT).
We did not find significant differences between the
different subgroups of experts except for the last case
were the physicians who were involved in the diagnosis
(radiologists and nuclear medicine physician) showed a
better IOA (kappa: 0.64)
Conclusion
The IOA was very good among the cases were the tumor
was well defined. Yet, in complex cases were the tumor
did not show the typical characteristics or in cases with
lipiodol deposits inter-observer agreement was
compromised.