TY - JOUR
T1 - MRI-guided stereotactic ablative radiation therapy of spinal bone metastases
T2 - A preliminary experience
AU - Llorente, Ricardo
AU - Spieler, Benjamin O.
AU - Victoria, James
AU - Takita, Cristiane
AU - Yechieli, Raphael
AU - Ford, John C.
AU - Brown, Karen
AU - Samuels, Michael A.
AU - Mellon, Eric A.
N1 - Funding Information:
James Victoria, CMD is an employee of Viewray, Inc Eric A Mellon, MD, PhD has received travel funding for presentation of unrelated data from Viewray in 2016 This work was supported by the Sylvester Comprehensive Cancer Center and Department of Radiation Oncology of the Miller School of Medicine of the University of Miami
Funding Information:
Research reported in this publication was supported by the National Cancer Institute of the National Institutes of Health under Award Number K12 CA226330. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
Publisher Copyright:
© 2020 The Authors. Published by the British Institute of Radiology
PY - 2020
Y1 - 2020
N2 - Objective: MRI provides clear visualization of spinal cord, tumor, and bone for patient positioning and verification during MRI-guided radiotherapy (MRI-RT). Therefore, we wished to evaluate spine stereotactic ablative radiotherapy (SABR) feasibility with MRI-RT. Given dosimetric limitations of first generation Co-60 MRI-RT, we then evaluated improvements by newer linear accelerator (linac) MRI-RT. Methods: Nine spinal metastases were treated with Co-60 MRI-RT. Seven received a single 16 Gy fraction, and two received three fractions totaling 24 or 30 Gy. After replanning with linac MRI-RT software, comparisons of organ at risk and dose spillage objectives between Co-60 and linac plans were performed. results: Spinal cord and cauda equina dose constraints were met in all Co-60 cases. Treatments were delivered successfully with real-time imaging during treatment and no treatment-related toxicities. While limits for dose spillage into surrounding soft tissues were not achieved due to the limitations of the Co-60 system, this could be corrected with linac MRI-RT delivery. Conclusions: MRI-RT SABR of spinal metastases is feasible with Co-60 MRI-RT. Dose delivery is improved by linac MRI-RT. advances in knowledge: This is the first report of MRI-RT for SABR of spinal metastases. The enhanced visualization of anatomy by MRI may facilitate RT dose escalation for spine SABR.
AB - Objective: MRI provides clear visualization of spinal cord, tumor, and bone for patient positioning and verification during MRI-guided radiotherapy (MRI-RT). Therefore, we wished to evaluate spine stereotactic ablative radiotherapy (SABR) feasibility with MRI-RT. Given dosimetric limitations of first generation Co-60 MRI-RT, we then evaluated improvements by newer linear accelerator (linac) MRI-RT. Methods: Nine spinal metastases were treated with Co-60 MRI-RT. Seven received a single 16 Gy fraction, and two received three fractions totaling 24 or 30 Gy. After replanning with linac MRI-RT software, comparisons of organ at risk and dose spillage objectives between Co-60 and linac plans were performed. results: Spinal cord and cauda equina dose constraints were met in all Co-60 cases. Treatments were delivered successfully with real-time imaging during treatment and no treatment-related toxicities. While limits for dose spillage into surrounding soft tissues were not achieved due to the limitations of the Co-60 system, this could be corrected with linac MRI-RT delivery. Conclusions: MRI-RT SABR of spinal metastases is feasible with Co-60 MRI-RT. Dose delivery is improved by linac MRI-RT. advances in knowledge: This is the first report of MRI-RT for SABR of spinal metastases. The enhanced visualization of anatomy by MRI may facilitate RT dose escalation for spine SABR.
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U2 - 10.1259/bjr.20190655
DO - 10.1259/bjr.20190655
M3 - Article
C2 - 31670569
AN - SCOPUS:85076448047
VL - 93
JO - British Journal of Radiology
JF - British Journal of Radiology
SN - 0007-1285
IS - 1105
M1 - 20190655
ER -