Interfraction Prostate Movement in Bone Alignment After Rectal Enema for Radiotherapy
서영은, 김태효, 이기수, 조원열, 허원주, 이형식, 최영민,
소속 상세정보
서영은 ( Seo Young-Eun )
Dong-A University College of Medicine Department of Urology
김태효 ( Kim Tae-Hyo )
Dong-A University College of Medicine Department of Urology
이기수 ( Lee Ki-Soo )
Dong-A University College of Medicine Department of Urology
조원열 ( Cho Won-Yeol )
Dong-A University College of Medicine Department of Urology
허원주 ( Hur Won-Joo )
Dong-A University College of Medicine Department of Radiation Oncology
이형식 ( Lee Hyung-Sik )
Dong-A University College of Medicine Department of Radiation Oncology
최영민 ( Choi Young-Min )
Dong-A University College of Medicine Department of Radiation Oncology
KMID : 0358320140550010023
Abstract
Purpose: To assess the effect of a rectal enema on interfraction prostate movement in bone alignment (BA) for prostate radiotherapy (RT), we analyzed the spatial difference in prostates in a bone-matched setup.
Materials and Methods: We performed BA retrospectively with data from prostate cancer patients who underwent image-guided RT (IGRT). The prostate was identified with implanted fiducial markers. The setup for the IGRT was conducted with the matching of three fiducial markers on RT planning computed tomography images and those on two oblique kV x-ray images. Offline BA was performed at the same position. The coordinates of a virtual prostate in BA and a real prostate were obtained by use of the ExaxTrac/NovalisBody system, and the distance between them was calculated as the spatial difference. Interfraction prostate displacement was drawn from the comparison of the spatial differences.
Results: A total of 15 patients with localized prostate cancer treated with curative hypofractionated IGRT were enrolled. A total of 420 fractions were analyzed. The mean of the interfraction prostate displacements after BA was 3.12±2.00 mm (range, 0.20-10.53 mm). The directional difference was profound in the anterior-posterior and supero-inferior directions (2.14±1.73 mm and 1.97±1.44 mm, respectively) compared with the right-left direction (0.26±0.22 mm, p<0.05). The required margin around the clinical target volume was 4.97 mm with the formula of van Herk et al.
Conclusions: The interfraction prostate displacement was less frequent when a rectal enema was performed before the procedure. A rectal enema can be used to reduce interfraction prostate displacement and resulting clinical target volume-to-planning target volume margin.
키워드
Displacement; Enema; Image guided radiotherapy; Prostate neoplasms
원문 및 링크아웃 정보
등재저널 정보