Planning DCE-MRI studies Because the intricacies of DCE-MRI allow measurement variability to be introduced at numerous points, study protocol must
be appropriately designed and strict quality control procedures must be followed. Due to the complexity of the imaging process,
the choice of an imaging facility is critical to the success of the DCE-MRI study. Although many imaging centers use the 1.5 Tesla MRI scanner, the image acquisition process is much more complicated than conventional
MRI techniques. Imaging technologists must be specifically trained in the imaging protocols to produce high-quality images,
minimize variance, and ensure accuracy. The imaging technologist must pay special attention to precontrast scanning, contrast
injection rate, and dosage and image timing and analysis. The DCE-MRI technique is most effective for studying areas of the body that are not impacted by involuntary patient movement,
such as the central nervous system, pancreas, breast, brain, and bone marrow. Lung and liver tumors are more challenging because
they are influenced by respiratory-related motion, leading to motion artifact. In such cases, patient movement should be incorporated
into the clinical study design, including variables such as sample size, patient recruitment or exclusion criteria to filter
out high-risk patients. In addition, imaging equipment and software in multicenter trials requires standardization of equipment and uniform image
acquisition across all sites. For this reason, single center trials are more feasible than multicenter trials. If a multi-center
trial is needed, an imaging CRO should be selected based on its ability to manage data from multiple sites and modality vendors,
and should be able to qualify hardware and software very early in the trial process. Likewise, a standardized reading process should use independent physician readers who have received specialized training in
reading and analyzing DCE-MRI images, including inter- and intravariability training prior to reading any studies. A centralized
reading process ensures that the same software and analysis techniques are used by all radiologists. Summary DCE-MRI is an important emerging imaging technology in the research and development of emerging vascular-targeted cancer therapies,
which prevent blood flow to and from the tumor. Because it provides visualization of the tumor's vasculature, allows blood
flow to be quantified and measured rapidly, and shows earlier tumor response to treatment, DCE-MRI is a more effective biomarker
than tumor shrinkage for studies of anti-angiogenic and vascular disrupting compounds. Although DCE-MRI studies use standard
MRI scanning equipment, the image acquisition process is much more intricate than for conventional MRI scans. As vascular-targeted cancer therapies advance and more compounds are developed, the role of DCE-MRI technology in cancer trials
will grow. Thorough study planning and protocol design, including careful training of imaging technologists and physician
readers, is required to ensure high-quality images and accurate readings, as well as to minimize variance. Dr. Stephen Pomeranz is the founder, chief executive officer, and medical director of ProScan Imaging, Inc., and ProScan MRI Education Foundation,
and the chief medical officer at WorldCare Clinical. Dr. Resham Mendi* is a senior radiology resident at the University of Illinois at Chicago and a research assistant at ProScan Imaging Midtown,
5400 Kennedy Avenue, Cincinnati, OH 45213, email: rrmendi@proscan.com
*To whom all correspondence should be addressed.
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