TITLE:
Lung Stereotactic Body Radiotherapy Using an Abdominal Compression System, “Air-Bag System”
AUTHORS:
Hideharu Miura, Ryoong-Jin Oh, Norihisa Masai, Hiroya Shiomi, Kouichi Yamada, Toshihiko Inoue
KEYWORDS:
Stereotactic Body Radiotherapy, Lung Cancer, Tumor Motion, Abdominal Compression, Air-Bag System
JOURNAL NAME:
International Journal of Medical Physics, Clinical Engineering and Radiation Oncology,
Vol.3 No.2,
May
20,
2014
ABSTRACT: We investigated respiratory
tumor motion in lung stereotactic body radiotherapy (SBRT) with use of the “Air-Bag
System”. 114 patients underwent four-dimensional (4D) computed tomography (CT)
from October 2010 to April 2012. Gross tumor volume (GTV) was 8.1 ± 11.0 cc (range
0.3 - 77.5 cc). The tumor site was the upper and middle lobes in 62 cases, and
lower lobe in 52 cases. The Air-Bag SystemTM consists of an inelastic
air bag connected to a second smaller elastic air bag. The inelastic air bag is
placed between the patient’s body surface and a HipFix and is secured by
pressure adjustment via the elastic air bag. To assess respiratory tumor
motion, the centroid of the tumor position is measured in the left-right,
anterior-posterior, and caudal-cranial directions using the iPlan RT DoseTM treatment planning system. Respiratory tumor motion vector for patients with
upper/middle and lower lobe tumors was 3.0 ± 2.2 mm (range, 0.4 - 11.7 mm) and
6.5 ± 4.6 mm (range, 0.4 - 22.0 mm) respectively, with this difference being
significant (p