UCLA Journal of Radiation Oncology APRIL 2023 - Flipbook - Page 17
UCLA RADIATION ONCOLOGY JOURNAL
conducted with both arms using the same
technology would be significantly more
straightforward to execute, in theory. However,
to our knowledge, no such trial has been
launched. We are actively exploring other
aspects of treatment delivery, such as the
frequency of beam-holds necessary due to
prostate motion, which might be important
factors with respect toxicity. We will also be
reporting data on long-term side effects and
oncologic outcomes.
trial has shown us that the benefits of physical
precision are not illusory, but tangible. ☐
In summary, the MIRAGE trial primary analysis
demonstrates that the use of MRI-guidance
in the context of prostate SBRT leads to
reduced physician-scored and patient-reported
urinary and bowel toxicity. This advantage
is attributable to the fact that MRI-guidance
allows enhanced physical precision, with a 2
mm PTV margin around the prostate being
targeted rather than a standard-of-care 4 mm
PTV margin.
for patients with prostate cancer. He has received grant
Based on the positive results of the MIRAGE
trial, we have changed our practice to
offering MRI-guided SBRT as our preferred
institutional standard of care. Patients who
have implanted metallic objects or shrapnel,
are extremely claustrophobic, or are completely
pacemaker-dependent are not candidates for
MRI-guided SBRT and still receive CT-guided
SBRT (with 4 mm margins). Patients with
minor claustrophobia, or who have implanted
devices that are MRI compatible, can be treated
with anxiolytic medications and appropriate
supervision.
Perhaps the biggest takeaway from the trial is
that as we enter the era of precision medicine
in oncology, our definition of precision can and
should extend beyond the biological precision
that comes from a deeper understanding of
cancer physiology. The physical precision of
improved radiation planning and delivery
devices, such as MRI-guided radiotherapy
platforms, can also translate into meaningful
benefits for patients. Indeed, the MIRAGE
Amar Kishan is an Associate Professor of Radiation and
Urology at the University of California, Los Angeles. He
also serves as the Vice Chair of Clinical and Translational
Research within the Department of Radiation Oncology. He is
responsible for running a clinical service focused on treating
patients with genitourinary malignancies, as well as leading
a clinical and translational research program designed to
improve post-treatment quality of life and treatment efficacy
funding from the Department of Defense, the American Society
for Radiation Oncology, the Prostate Cancer Foundation, the
National Institutes of Health, and Kure-It. He has also received
research support from ViewRay Inc. (outside the scope of the
MIRAGE Trial), as well as honoraria from ViewRay Inc.
References
NCI Dictionary of Cancer Terms. (https://www.cancer.gov/
publications/dictionaries/cancer-terms/def/precision-medicine).
1 Teckie S, McCloskey SA, Steinberg ML. Value: a framework for
radiation oncology. J Clin Oncol 2014;32(26):2864-70. (In eng).
DOI: 10.1200/jco.2014.55.1150.
2 Hoffman KE, Penson DF, Zhao Z, et al. Patient-Reported
Outcomes Through 5 Years for Active Surveillance, Surgery,
Brachytherapy, or External Beam Radiation With or Without
Androgen Deprivation Therapy for Localized Prostate
Cancer. Jama 2020;323(2):149-163. (In eng). DOI: 10.1001/
jama.2019.20675.
3 Donovan JL, Hamdy FC, Lane JA, et al. Patient-Reported
Outcomes after Monitoring, Surgery, or Radiotherapy for
Prostate Cancer. The New England journal of medicine
2016;375(15):1425-1437. (In eng). DOI: 10.1056/NEJMoa1606221.
4 Wei JT, Dunn RL, Litwin MS, Sandler HM, Sanda MG.
Development and validation of the expanded prostate cancer
index composite (EPIC) for comprehensive assessment of
health-related quality of life in men with prostate cancer.
Urology 2000;56(6):899-905. (In eng). DOI: 10.1016/s00904295(00)00858-x.
5 Kishan AU, Ma TM, Lamb JM, et al. Magnetic Resonance
Imaging-Guided vs Computed Tomography-Guided Stereotactic
Body Radiotherapy for Prostate Cancer: The MIRAGE
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