ESTRO 36 Abstract Book

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S350 ESTRO 36 2017
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equivalent dose (BED), fractionation schedule of SBRT,
size of largest metastasis, development of local
recurrence after SBRT, delay in initiation of SBRT for ≥ 4
months, presence of comorbidity, location of lung
metastasis: central versus peripheral and location of
metastasis in lower lobes versus other locations. Primary
tumors included 117 colorectal tumors, 36 lung cancers,
11 melanoma, 10 sarcoma, 7 breast carcinoma and 25
tumors were from other sites. Median follow up was 23
months (range 1-100).
Results
Median survival in the entire cohort was 32 months. The
2, 3, and 5 year OS rate was 63%, 47%, and 30%,
respectively. On univariate analysis, synchronous
metastasis and colorectal primary site were significantly
associated with improved OS. On multivariate analysis,
presence of synchronous metastasis was the only factor
independently associated with better OS, adjusted
HR=0.57 (95% CI 0.36-0.89). On further categorization,
there was significant difference (p =0.048) among
synchronous liver metastasis that later developed
pulmonary oligorecurrence (median OS 63 months),
synchronous pulmonary oligometastasis (Median OS 40
months) and metachronous pulmonary oligometastasis
(Median OS 29 months).Local control for the entire group
was at 2, 3, and 5 year was 83%, 79% and 73%, respectively.
Less than 2% of patients experienced grade 3 acute or late
toxicities.
Conclusion
SBRT to pulmonary oligometastasis resulted in a 5 year
survival of 30%. Synchronous metastases were
independently associated with better OS.
PO-0677 Vero SBRT for early stage lung cancer: a phase
II trial with dynamic tracking in selected lesions
C. Collen 1, R. Van den Begin1, M. Boussaer1, B. Engels 1, J.
Dhont1, M. Burghelea1, G. Storme1, M. De Ridder 1
1 Universitair Ziekenhuis Brussel, Department of Radiation
Oncology, Brussels, Belgium
Purpose or Objective
To evaluate outcome and toxicity after Vero stereotactic
body radiotherapy (SBRT) in early stage lung cancer, and
feasibility of dynamic tumor tracking (DTT) with a single
fiducial marker in this population.
Material and Methods
A prospective trial (NCT 02224547) was started to evaluate
SBRT on a gimbaled linac (Vero) for early stage non-small
cell lung cancer (T1-3N0M0).
Patients were eligible for DTT if tumor motion on
pretreatment 4DCT exceeded 8 mm. A single fiducial
marker (Visicoil, IBA) was implanted percutaneously in or
near the tumor. Otherwise an internal target volume (ITV)
approach was applied, combining GTV’s of all 10
respiratory phases on 4DCT. For both approaches, an PTV-
margin of 5mm was used from GTV (DTT) or ITV.
Results
A total of 73 lesions were treated in 68 patients between
Feb 2013 and Feb 2016. Median follow-up amounted to 11
months (2-28 months). Histology was available in 64% of
patients, of which 66% were adenocarcinomas and 30%
squamous cell carcinomas.
Delivered dose schedules were 48Gy/4 fractions (n= 59),
51Gy/3 fractions (n= 9), 60Gy/8 fractions (n= 5). In 12% of
lesions DTT was used. Reasons for omitting DTT were: poor
baseline pulmonary function (n=7), deep location not
allowing visicoil insertion (n=3), presence of a visicoil in
the other lung (n=1) and history of prior pneumothorax
(n=1). Mean treatment time for a DTT session was 28.6
minutes, comparable with the mean ITV treatment time
(29.5min). Use of DTT resulted in an average PTV
reduction of 32% (10-48%) compared to corresponding ITV
plans (p=0.004).
Two patients needed a temporary chest tube for a small
pneumothorax after marker implantation, but no
radiotherapy toxicity was observed in the patients treated
with DTT. In the ITV group, only 1 patient experienced a
grade 2 radiation pneumonitis and 2 patients presented
with a COPD exacerbation in the weeks following RT.
In DTT lesions, our results also demonstrated a significant
variability in respiration-induced tumor motion: mean
craniocaudal motion measured on 4DCT was 13.1mm ±
3.5mm, while during treatment delivery a mean maximum
value of 18.9mm ± 8.0mm was observed (p=0.04).
One-year Kaplan-Meier outcome analysis shows a local
control of 97%, a progression-free survival of 84% and an
overall survival of 91%, with no differences between the
DTT and ITV groups.
Conclusion
Vero SBRT demonstrated excellent outcomes and limited
toxicity in early stage lung cancer. Compared to ITV, DTT
offered a smaller irradiated volume and allowed adaption
to intrafraction movements not covered by 4DCT. DTT by
use of a single marker is feasible in primary lung cancer
patients, but the need for an implanted marker limits
applicability in this population.
PO-0678 Health-related quality of life reporting in lung
cancer trials: A methodological appraisal.
L. Van der Weijst1, V. Surmont2, W. Schrauwen3, Y.
Lievens4
1Ghent University Hospital, Radiation Oncology and
Experimental Cancer Research, Gent, Belgium
2Ghent University Hospital, Pneumology, Gent, Belgium
3Ghent University Hospital, Medical Psychology, Gent,
Belgium
4Ghent University Hospital, Radation Oncology and
Experimental Cancer Research, Ghent, Belgium
Purpose or Objective
Health-related quality of life (HRQoL) is an important
outcome measurement in locally-advanced non-small cell
lung cancer (LA-NSCLC) patients, often presenting
considerable comorbidities, hence in clinical trials
assessing the role of radiotherapy in this patient
population. In addition to the correct execution of these
HRQoL studies, it is equally important that the HRQoL
data, retrieved from these clinical trials, are reported in
a standardized manner, as to draw correct conclusions to
support treatment decisions. The aim of this study is to
examine the methodological quality of HRQoL reporting in
a series of studies retrieved through a systematic review
of the literature.
Material and Methods
A literature search was performed in PubMed, Embase and
Web of Science, with the following inclusion criteria:
English language, clinical trial, LA-NSCLC patient
population, HRQoL assessment, full-text availability and
published between 2005 – 2015. The methodological
quality of each study was assessed by the standard
checklist for the quality of HRQoL reporting in cancer
clinical trials [Efficace et al. J Clin Oncol 2003;21:3502-