ESTRO 36 Abstract Book

561 / 1082

S546 ESTRO 36 2017
_______________________________________________________________________________________________
used for radiotherapy and to eliminate the errors caused
by curvature change.
Material and Methods
With the agreement of institutional review board, 71 head
and neck patients were enrolled and randomly assigned to
use different pillow for either primary or postoperative
RT. The three different pillows including conventional
pillow (CP, Silverman Headrests, CIVCO, medical
solution), customized pillow with alpha cradle (AC,
Smithers Medical Products, Inc. ), and Moldcare Head
Cushion pillow (MP, Alcar Co, Inc.). All patients used head
and shoulder mask for fixation. Daily on-board image (OBI)
was acquired for evaluation and correction of set-up error.
Change of curvature was measured by the movement of
the vertebral body of first (C1) and 5th (C5) cervical spine,
comparing to the location on digital reconstructed image
from CT simulation.
Results
Of all patients accrued, 34 patients received surgery and
postoperative radiotherapy, and 13, 11, and 10 patients
used CP, AC, and MP respectively. Thirty-seven patients
received primary radiotherapy without surgery, and 14,
11, and 12 of them used CP, AC, and MP respectively.
There were 1633 OBI acquired. In postoperative RT group,
the absolute movement of C1 were 0.07±0.03 cm,
0.07±0.03 cm, and 0.09±0.03 cm, when CP, AC, and MP
was used, respectively (p> 0.05). In RT group, the absolute
movements of C1 were 0.07±0.03 cm, 0.06±0.02 cm, and
0.08±0.08 cm, when CP, AC, and MP were used,
respectively (p> 0.05). In comparison the movement of C5,
the absolute movements were 0.15±0.04, 0.21±0.07, and
0.16±0.72, when CP, AC, and MP was used in postoperative
RT group, respectively (p> 0.05). In primary RT group, the
absolute movements were 0.23±0.09, 0.14±0.05, and
0.15±0.03, when CP, AC, and MP was used, respectively.
The movements of C5 in patients who used AC (p = 0.048)
or MP (p = 0.05) were significant lower than patients who
used CP in primary RT group.
Conclusion
Customized pillow could reduce setup error in patients
who received primary radiotherapy but not postoperative
radiotherapy.
PO-0999 Control of rectal volume with Kampo formula
during prostate radiotherapy: A prospective study
J. Kobayashi1, T. Tahara2, Y. Matsuzaki1, Y. Ono1, J.
Matsumoto1, H. Sato 1, K. Onko1, Y. Kishimoto1, T.
Tanino 2, H. Sakaguchi2, N. Uchida2
1 Tottori University Hospital, Radiology, Yonago, Japan
2 Tottori University Hospital, Radiation Oncology,
Yonago, Japan
Purpose or Objective
During intensity-modulated radiation therapy (IMRT) for
prostate cancer, volume and position of the prostatic
gland, bladder and rectum should be kept stable to
minimize adverse events such as radiation proctitis or
rectal bleeding. For this purpose, keeping the rectal
volume small is essential. Daikenchuto (DKT) is a
traditional Japanese herbal (Kampo) formula used to treat
patients with abdominal bloating or constipation and is
reported to increase intestinal motility. DKT is composed
of three medical herbs (ginger, ginseng radix, Japanese
pepper) and maltose powder. The purpose of this study
was to investigate the effect of DKT on rectal volume
during prostate IMRT prospectively.
Material and Methods
The institutional review board approved this study and
written informed consent was obtained from all patients.
We divided consecutive 30 non-metastatic (cT1cN0 to
cT3bN0) prostate cancer patients into two groups. 15
patients were orally administered 15 grams of DKT per day
from one month before IMRT until the last day of the
treatment (DKT group). The remaining 15 were not
administered DKT (non-DKT group). The prescribed
radiation dose was 78 Gy in 39 fractions for 7.5 weeks to
the prostatic gland and proximal one-third or entire
seminal vesicle according to their stratified recurrence
risk. Kilo-voltage computed tomographic image (KV-CT) by
linear accelerator (Trilogy, Varian Co.) was taken for
three-dimensional matching set-up before each treatment
session. Each KV-CT was sent to a radiation treatment
planning workstation (Pinnacle 3, Phillips Medical Systems
Co.) and rectal volume of anal-sided 8cm length was then
measured. Calculated rectal volumes of the DKT group
were compared to those of the non-DKT group.
Administration of laxative agent, tubal gas suction or
colon irrigation was done depending on residual rectal
content before radiation.
Results
Total of 1,170 KV-CT were evaluated. Rectal volumes of
DKT and non-DKT groups were 48.79-63.46 (mean 54.69
+/- 4.00) cm3 and 52.41-142.57 (mean 81.37 +/- 16.36)
cm3, respectively (p < 0.01). Adverse effects associated
with DKT use such as appetite loss, liver dysfunction or
interstitial pneumonia were not noted.
Conclusion
DKT appears to be useful in reducing rectal volume and
intra-fractional volume variance which would help prevent
radiation proctitis or rectal bleeding in prostate curative
radiotherapy. Longer follow-up with a larger patient
population is desired.
PO-1000 Immobilisation systems for brain treatment:
are individual head supports needed for stable fixation?
S. Meessen1, F. De Beer1, P. Van Haaren1, D. Schuring1
1Catharina Hospital Eindhoven, Department of Radiation
Oncology, Eindhoven, The Netherlands
Purpose or Objective
For stereotactic treatment of brain metastases, good
fixation of the patient is necessary to enable the use of
small PTV margins and reduce the volume of healthy brain
tissue receiving high doses. These fixations should prevent
significant intrafaction movement, and reduce the
interfraction rotations. The purpose of this study was to
compare three different fixation systems, two with
individual head supports and one with standard head
support, and to evaluate which of these systems was best
suited for stereotactic brain treatments.
Material and Methods
Patients receiving brain RT were treated with either one
of three different fixation systems (Orfit Industries, see
figure 1): a hybrid mask combined with (a) an individual
head support vacuum bag (n=20); (b) a Thermofit
individual head support(n=17); (c) a standard 3D head
support with cranial stop (n=10). All patients received a
correction protocol and were imaged at least 3 times
during the treatment course using an Elekta XVI CBCT,
both before and at the end of the treatment fraction. All
scans were registered on bony anatomy and translations
and rotations were recorded and analysed. For the three