ESTRO 36 Abstract Book

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S275 ESTRO 36 2017
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outcomes of SBRT for unresectable liver metastases and
to analyze prognostic factors affecting OS of these
selected oligometastatic patients.
Material and Methods
Patients with 1 to 3 unresectable liver metastases, with
maximum individual tumor diameters less than 6 cm and a
Karnofsky Performance Status of at least 70, were enrolled
and treated by SBRT on a phase 2 clinical trial. Dose
prescription was 75 Gy on 3 consecutive fractions. SBRT
was delivered using the volumetric modulated arc therapy
by RapidArc (Varian, Palo Alto, CA) technique. Primary
end point was in field local control (LC), secondary end
points were overall survival (OS), progression free survival
(PFS) and toxicity.
Results
Between February 2010 and September 2011, a total of 61
patients with 76 lesions were enrolled in this phase II trial,
with a median follow-up time of 1.9 years. One-, three-
and five- years LC rates were 94%, 78% and 78 %,
respectively, with a median LC of 1.7 years. Median OS
was 2.3 years and the survival rates were 83%, 30%
and 21% at 1, 3 and 5 years, respectively. Univariate
analysis showed two independent positive prognostic
factors affecting survival: female sex (p = 0.012) and
primary tumour (p = 0.001). Toxicity was moderate. One
patient experienced G3 late chest wall pain, which
resolved within 1 year from SBRT. No cases of RILD were
detected.
Conclusion
Long-term results of this Phase II study suggest the
efficacy and safety of SBRT for unresectable liver
metastases at 5 years of follow-up. Selection of cases with
positive prognostic factors may improve long-term survival
of these oligometastastic patients and may confirm the
role of SBRT as an effective alternative local therapy for
liver metastases.
OC-0525 Factors affecting local control for pulmonary
oligometastasis treated with SBRT
A. Sharma 1, M. Duijm1, E. Oomen-de Hoop2, J. Aerts3, C.
Verhoef 4, M. Hoogeman1, J. Nuyttens1
1 Erasmus MC-Daniel den Hoed Cancer Center-
Rotterdam- The Netherlands, Department of Radiation
Oncology, Rotterdam, The Netherlands
2 Erasmus MC-Daniel den Hoed Cancer Center-
Rotterdam- The Netherlands, Department of Medical
Oncology, Rotterdam, The Netherlands
3 Erasmus MC-Daniel den Hoed Cancer Center-
Rotterdam- The Netherlands, Department of
Pulmonology, Rotterdam, The Netherlands
4 Erasmus MC-Daniel den Hoed Cancer Center-
Rotterdam- The Netherlands, Department of Surgical
Oncology, Rotterdam, The Netherlands
Purpose or Objective
To evaluate local control (LC) and identify factors
associated with LC for inoperable pulmonary
oligometastases treated with stereotactic body
radiotherapy (SBRT).
Material and Methods
In 206 patients, 326 pulmonary oligometastasis were
treated with SBRT. Oligometastatic tumors were defined
as ≤ 5 metastases in no more than two organs at time of
treatment. Metastases were categorized as synchronous if
metastases developed within 5 months of diagnosis of
primary tumor, else were assigned to metachronous
group. SBRT schedule depended on location of metastasis,
its size and dose calculation algorithm. Dose to PTV was
prescribed at 70-90% isodose line (median 78%), covering
at least 95% of the PTV. LC was calculated from first
session of SBRT to date of local recurrence. Patients
without any local recurrence at date of last follow up
were censored. Variables assessed as prognostic factors
for LC included: metachronous versus synchronous
metastasis, pre SBRT chemotherapy, primary
site, location in lower lobes versus other, central and
peripheral lung metastasis, tumor size, single versus
fractionated SBRT, BED, algorithm used, delay in SBRT.
Toxicity was recorded as per NCI CTCAE, version 3.0.
Ninety per cent of pulmonary oligometastasis were
treated with BED>100 and with fractionated SBRT. Two
hundred and thirty nine oligometastases were peripheral
in location and majority (258) were <3 cm in diameter.
Primary tumor site included 117 colorectal tumors, 36 lung
cancers, 11 melanoma,10 sarcoma, 7 breast carcinoma,
and 25 metastases were from other sites. Median follow
up was 22 months (range 1-100).
Results
LC at 2 and 5 years was 83% and 73%, respectively. On
univariate analysis BED <100 (HR=3.08), single fraction
radiotherapy (HR=2.81), synchronous metastasis
(HR=2.13), pre SBRT chemotherapy (HR=2.83), and SBRT
delay > 4 months (HR=2.49) were significantly associated
with inferior LC. At BED >100 synchronous metastasis (2
year LC 76% vs 88%), pre SBRT chemotherapy (2 year LC
78% vs 91%), and SBRT delay >4months (2 year LC 79% vs
90%) were significantly associated with lower LC rate. On
multivariate analysis BED <100 (HR 4.36), single fraction
radiotherapy (HR 4.02), pre SBRT chemotherapy (HR
2.32), synchronous metastasis (HR 2.16), and SBRT delay
>4 months (HR 2.17) remained independently associated
with lower LC. Median OS in entire cohort was 32
months. The 2, 3, and 5 year OS rates were 63%, 47% and
30%, respectively. Less than 2% of patients experienced
grade 3 acute or late toxicities. There were no grade 4 and
5 events.
Conclusion
The study identified 5 factors independently associated
with inferior LC. Despite BED >100 synchronous metastasis,
pre SBRT chemotherapy and SBRT delays were
significantly associated with inferior LC rate. These
findings will help to refine SBRT practice for pulmonary
oligometastasis.
OC-0526 Quality of life after SBRT in bone metastases:
analysis from the prospective PRESENT cohort
G. Fanetti1, A.S. Gerlich2, E. Seravalli2, H.M. Verkooijen3,
M. Van Vulpen2, R. Orecchia4, B.A. Jereczek-Fossa1, J.
Van der Velden2
1European Institute of Oncology - University of Milan,
Department of Radiation Oncology, Milan, Italy
2University Medical Center, Department of Radiation
Oncology, Utrecht, The Netherlands
3University Medical Center, Julius Center for Health
Sciences and Primary Care, Utrecht, The Netherlands
4European Institute of Oncology - University of Milan,
Scientific Directorate, Milan, Italy
Purpose or Objective
Stereotactic body radiotherapy (SBRT) is an emerging
treatment in patients with bone metastases (BM). Local
control is achieved in up to 95% of lesions and up to 80%
of patients experience pain relief after SBRT. However, in
patients with a limited life expectancy, quality of life