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follow-up of 20 months, the median PFS was 20 months.
One-year, two-year PFS and three-year PFS were 70%, 53%
and 42%, respectively. Two-year and three-year LC were
95% and 79%, respectively. Two-year and three-year MFS
were 53% and 42%, respectively (median, 20 months).
Median OS was 19.2 months.One-year OS, two-year OS and
three-year OS were 77%, 47% and 37%, respectively. The
median OS for borderline resectable patients was 21.5
months compared with 14 months for unresectable
patients (p=0.3). Patients who underwent resection had a
significantly longer median OS compared with non-
resected patients (37.6 months vs 13 months, p=0.03).
Conclusion
This protocol treatment represents a well-tolerated
promising approach for patients with borderline
resectable and unresectable pancreatic cancer. Continued
optimization in multimodality therapy and an accurate
patient selection are crucial for the appropriate treatment
of patients.
PO-0699 Is stereotactic radiotherapy following
radiochemotherapy useful in local advanced pancreatic
cancer?
G. Mattiucci
1
, A. Nardangeli
1
, L. Boldrini
1
, M. Balducci
1
,
F. Cellini
1
, S. Chiesa
1
, G. Chiloiro
1
, F. Deodato
2
, N.
Dinapoli
1
, V. Frascino
1
, M. Gambacorta
1
, G. Macchia
2
, A.
Morganti
3
, V. Valentini
1
1
Università Cattolica del Sacro Cuore- Gemelli ART,
Radiation Oncology, Rome, Italy
2
Fondazione “Giovanni Paolo II”- Università Cattolica del
Sacro Cuore, Radiotherapy Unit, Campobasso, Italy
3
Università di Bologna- Ospedale S. Orsola-Malpighi,
Radiation Oncology Center- Department of
Experimental- Diagnostic and Specialty Medicine – DIMES,
Bologna, Italy
Purpose or Objective
To evaluate the feasibility and efficacy of stereobody
radiotherapy (SBRT), following radiochemotherapy (RTCT)
and chemotherapy (CT), in patients (pts) with
unresectable, locally advanced pancreatic carcinoma
(LAPC). Primary endpoints were toxicity, local control (LC)
and pain-free progression (PFP); secondary endpoints
were overall survival (OS) and disease-free survival (DFS).
Material and Methods
Patients affected by unresectable LAPC already treated
with RTCT (50.4 Gy in 28 fractions (fr) to visible pancreatic
tumour and 39.6 Gy in 22 fr to nodal drainage area with
concurrent gemcitabine) and chemotherapy (Gemcitabine
or Folfirinox), with no evidence of metastatic disease at
the restaging imaging, were selected for a SBRT boost on
the primary lesion. The pain assessment was defined by
Kersh-Hazra scale.
Results
From 2003 to 2015, 26 consecutive pts (16 male, 10
female), with a median age of 65,5 years (range 47-80),
were enrolled in this study. The 53,8% was a cT4 and the
50% was a N1. The tumor was localized in the head of the
pancreas in 53.8% of pts. The SBRT boost was delivered to
the primary lesion with a total dose depending on the dose
received by the duodenum (maximum dose to the
duodenum 90Gy in EQD2 α/β 2 summing the dose received
during RT-CT and SBRT): 20Gy in 5 fr for 4 pts, 20Gy in 4
fr for 5 pts, 25Gy in 5fr for 16 pts and 30Gy in 6fr for 1pt.
The median follow up was 25 months (range 15-154). The
median interval between RTCT and SBRT was 8 months
(range 3-16 months). None Grade 3 or 4 acute or late
gastrointestinal toxicities were developed among all pts
after SBRT. Pain control was achieved in 19 pts (73,1%)
after SBRT boost. After SBRT: 2-years and 3-years LC were
62.4% and 41.6%, with a median of 36 months; 2-years and
3-years PFP were 64.3% and 32.1%, with a median of 25
months; 2-years and 3-years DFS were 27.8% and 18.5%,
with a median of 7 months. The 2-years and 3-years OS
after SBRT were 57% and 42.7%, with a median of 29
months. Since diagnosis: 2-years and 3-years LC rate were
71.1% and 64.6%, with a median of 45 months; the 2-years
and 3-years PFP were 86.3% and 49.3%, with a median of
35 months; 2-years and 3-years DFS were 45.8% and 29.7%,
with a median of 23 months; 2-years and 3-years OS was
77.3% and 58%, with a median of 41 months.
Conclusion
A SBRT boost on primary lesion after RTCT and CT could
be delivered safely and effectively in pts with non-
metastatic, unresectable LAPC with acceptable side
effects and with promising local and pain control.
PO-0700 Significant heart dose reduction by deep
inspiration breath hold for RT of esophageal cancer
M. Dieters
1
, J.C. Beukema
1
, A.C.M. Van den Bergh
1
, E.W.
Korevaar
1
, N.M. Sijtsema
1
, J.A. Langendijk
1
, C.T. Muijs
1
1
UMCG University Medical Center Groningen, Radiation
oncology, Groningen, The Netherlands
Purpose or Objective
As survival for esophageal cancer (EC) patients improves
1
,
reduction of long term radiation-induced toxicity will
become increasingly important. For radiotherapy of left-
sided breast cancer patients, deep inspiration breath-hold
is used routinely to minimize the radiation dose to the
heart
2
. For EC patients, the expiratory phase might be
more beneficial to reduce the heart dose, while the
inspiration phase might be better for the dose to the
lungs, consequently allowing for cardiac dose reduction.
Therefore, the main objective of this study was if breath
hold in photon radiotherapy of esophageal cancer
minimized the dose to the heart, without compromising
the dose to the lungs and the target.
References:
1. Shapiro J, van Lanschot JJB, Hulshof MCCM,
et
al.
Lancet Oncol.
2015;16:1090–1098.
2. Sixel KE, Aznar MC, Ung YC. Int J Radiat Oncol Biol Phys
2001;49:199–204.
Material and Methods
Ten EC patients were included in this in prospective cohort
study. All patients received a free breathing (FB) 4D-
plannings-CT and additionally a CT-scan in deep
inspiration (DIBH) and expiration breath-hold (EBH) using
Active Breathing Control (ABC). Treatment volumes and
organs at risk were delineated. No ITV margin was used in
the breath-hold CTs assuming absence of respiratory
movement. Full VMAT treatment plans (3 arcs, per arc
<20sec delivery time) were constructed on all 3 planning
CTs (FB, DIBH and EBH) with the aim to cover the target
with a prescribed dose of 41.4Gy or 50.4Gy, while
reducing the cardiac dose, without compromising the dose
to the lungs. These plans were compared to the clinically
robust partial VMAT /IMRT treatment plans (clinFB), for
volume and DVH differences using one way ANOVA with
Bonferroni correction.
Results
Breath-hold, both DIBH and EBH, was feasible in all
patients. The GTVs were similar on all 3 CT-scans(p=0.99).
With DIBH, lung volumes were significantly larger (on
average 2800 cc) than with FB andEBH (p<0.01). The mean
heart dose (MHD) and V30 heart were also significantly
different among the4 types of treatment plans (p=0.02 and
p<0.01) (table 1). The reduction of the MHD and V30
heartwere most pronounced using DIBH and was consistent
over the entire range of MHD/MLD, asillustrated by the
example in figure 1.b. On average, the MHD and V30 heart
reduced from 22Gy inthe clinFB plans to 13.8Gy in the
DIBH plans (mean difference 8.2Gy, 95%CI 1.2-15.3)
(figure 1.a). Thereduction in cardiac dose can be
explained by: 1) Use of full VMAT instead of partial
VMAT/IMRT, 2)the absence of ITV margin when using BH,
3), an increase of lung volume, which allows cardiac
dosereduction, corresponding to average MHD reductions
of 2.8 Gy (1), 2.2 Gy (2) and 3.2 Gy (3),respectively (figure
1.c).