ESTRO 36 Abstract Book

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S392 ESTRO 36
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Results
From 2000 to 2011, 121 patients (median age: 50 years,
range 16-86; median follow-up: 54 months), affected by
primary high grade STS, underwent unplanned surgery, re-
excision of the tumor bed (radicalization) within a
maximum of 3-6 months from the previous surgery,
perioperative BRT and adjuvant EBRT. Seventeen patients
(14.0%) developed metastases, 7 patients (5.8%) relapsed
and 9 out of 121 patients died (7.4%). Five-year LC and OS
were 93.0% and 91.6%, respectively. At univariate analysis
higher 5-year DFS and OS were recorded in patients with
lower- limb tumors vs upper-limb and trunk STS (p: 0.053
and 0.041, respectively). Although it wasn’t detected any
statistical significance related to histologies. Younger
patients (< median age) showed improved 5-year LC (97.9%
vs 88.1%, p: 0.052), 5-year DFS (88.9% vs 73.9%, p: 0.034)
and 5-year OS (96.5% vs 86.6%, p: 0.093).
Conclusion
The combination of BRT and EBRT is able to achieve
satisfactory results, with a high local control rate and
overall survival. Prospective studies on combined modality
treatment in the adjuvant setting of STS after re-excision
surgery or inadequate excision are still needed to improve
the results in STS of the trunk and limb.
Poster: Clinical track: Palliation
PO-0745 Intrafractional movement of patients with
spinal cord compression receiving radiation therapy
E. Ravnkilde1, I.M. Jakobsen 1, A. Appelt1, J.P.
Bangsgaard1, L.S. Fog1
1 Rigshospitalet, Clinic of Oncology, Copenhagen,
Denmark
Purpose or Objective
Many palliative radiation therapy patients experience
moderate to severe pain. This pain could potentially
increase intrafractional movement, requiring planning
treatment volume (PTV) margins to be adjusted to account
for this. We conducted a prospective study to examine the
impact of patient-experienced pain on intrafractional
movement and the time needed for treatment delivery.
Material and Methods
This prospective study included 18 consecutive patients
receiving radiation therapy for spinal cord compression.
We recorded the patients’ intrafractional shifts, the
treatment time, the treatment site and the patients’ self-
reported pain score. The patients were asked to assess
their pain (‘pain’) prior to radiation therapy fraction, on a
scale from 1 to 10 using the NRS (Numerical Ratings Scale)
[Pain Pract. 3 (4): 310–6] . Cone beam CT images were
acquired before and after all daily treatments. The
interfractional shift (‘shift’), linac ID number (‘linac’),
treatment time (‘time’), fraction number (‘’fr number’)
and treatment site (‘site’) were recorded. The average
and maximum shifts, and the standard deviation (s.d.),
were determined.
Spearman correlation coefficients were calculated
between: shift and time, fr number, or pain; time and fr
number or pain; pain and fr number. Since site was scored
by a categorical variable, a Kruskal Wallis test was used to
investigate effect of treatment site on shift, time or pain
score.
The patients provided informed consent to participation
in the study.
Results
A total of 113 shifts were measured. The average shift was
0.96 mm, the maximum 4.1mm, and the s.d. was 0.89 mm
(fig 1). The only significant correlations (see fig 2) were
between
- Shift and pain (patients reporting more pain had greater
shifts, p=0.0045, r=0.2699). Patients who report more pain
have greater intrafractional shifts. This may be due to
patient discomfort.
- Time and fr number (later fractions were completed
more quickly, p=0.0001, r=0-0.3500). The reduced time
for later fractions may be due to the patient becoming
more familiar with the treatment procedure.
- Pain and fr number (patients reported less pain in later
fractions , p=0.0412, r=-0.1960). While pain score
decreased with fraction number, fewer patients provided
pain scores for later fractions.
- Site and time (p=0.0044, C²=10.87). Treatment site
correlates with treatment time.
Patients with pain scores £5 had mean intrafractional shift
0.09 cm (s.d. 0.09), while patients with pain scores >5 had
mean shift 0.11 (s.d.0.07).
Conclusion
A 5 mm PTV margin appears sufficient to account for
intrafractional patient movement for spinal cord
compression patients imaged daily.
PO-0746 Inter-observer variation in GTV delineation of
bone metastases: a multicenter study
A.S. Gerlich1, J.M. Van der Velden1, A.N.T.J. Kotte1, C.L.
Tseng2, G. Fanetti3, W.S.C. Eppinga 1, N. Kasperts1,
M.P.W. Intven1, F.A. Pameijer 4, M.E.P. Philippens 1, H.M.
Verkooijen5, E. Seravalli1
1University Medical Center Utrecht, Radiation Oncology,
Utrecht, The Netherlands
2Sunnybrook Health Sciences Centre, Radiation Oncology,
Toronto, Canada
3European Institute of Oncology, Radiation Oncology,
Milan, Italy
4University Medical Center Utrecht, Radiology, Utrecht,
The Netherlands
5University Medical Center Utrecht, Imaging, Utrecht,
The Netherlands