Statistical evaluation of the effectiveness of dual amplitude-gated stereotactic body radiotherapy using fiducial markers and lung volume

Patient-specific respiratory motion management using lung tumors vs fiducial markers for real-time tumor-tracking stereotactic body radiotherapy

“…This study evaluated the effect of the differences in respiratory movement between the fiducial marker, which serves as a surrogate tumor marker, and the lung tumor. No correlation was found between the lung tumor-to-fiducial marker distance and the respiratory movement in each direction, which, in our opinion, indicates that the lung tumor-to-fiducial marker distance is not an appropriate index for selecting fiducial markers in treatment planning CT [12] . As shown in Fig.…”

“…The spatial coordinates of the fiducial marker may be displaced during SBRT, and the amplitude difference between the lung tumor and fiducial marker should be observed during SBRT [20] . In the future, we believe that more robust and dynamic tracking during SBRT may be realized by combining magnetic resonance imaging and respiration by lung volume in addition to fiducial marker [9] , [12] , [21] , [22] .…”

“…A previous study has reported on the effect of the dose on the distance of the spatial coordinates between a fiducial marker and a lung tumor in CT images of spontaneous expiratory arrest taken as a part of treatment planning and in matched images at the time of treatment [11] . In our previous study, we evaluated the respiratory movement relationship among lung tumor, lung volume, and fiducial markers and showed that the distance between lung tumor and fiducial marker was not correlated in respiratory movement [12] . However, it was not possible to evaluate the respiratory movement relationship between lung tumor and fiducial markers as well as the distance between lung tumor and fiducial markers in each direction focusing on fiducial markers alone [12] .…”

“…In our previous study, we evaluated the respiratory movement relationship among lung tumor, lung volume, and fiducial markers and showed that the distance between lung tumor and fiducial marker was not correlated in respiratory movement [12] . However, it was not possible to evaluate the respiratory movement relationship between lung tumor and fiducial markers as well as the distance between lung tumor and fiducial markers in each direction focusing on fiducial markers alone [12] . To date, no study has investigated the relationship between the 3D distance between a lung tumor and a fiducial marker and the interphase shift caused by respiratory movement at the time of dynamic tracking during lung SBRT to evaluate the effect of the fiducial marker on the gating window.…”

Real-time tumor-tracking radiotherapy with SyncTraX for primary liver tumors requiring isocenter shift

“…The positional relationship between the fiducial marker and tumor can also be altered by respiratory motion. In SBRT with a fiducial marker, the respiratory motion of the lung tumor and marker implanted near the tumor have been shown to be slightly different [ 15 , 23 , 24 ]. From their analysis of SBRT for lung tumors with SyncTraX, Tanabe et al .…”