The scope of molecular imaging is expanding. R &D efforts are making clinical inroads and the already invaluable tool for nuclear medicine and oncology applications is showing promise in cardiology and neurology applications. For patients, molecular imaging promises earlier, more accurate diagnoses as well as earlier, more effective therapy. To better understand what is on the horizon for molecular imaging, Health Imaging & IT spoke with Edward Coleman, MD, professor of Radiology, director of Nuclear Medicine and vice chair of the Department of Radiology at Duke University Medical Center, and president of the Academy of Molecular Imaging (AMI), about the current state and future of molecular imaging.
Coleman has published more than 400 scientific papers in several leading journals, authored 80 book chapters, and published seven textbooks on topics related to nuclear medicine. He has served as past chairman of the American Board of Nuclear Medicine, is a fellow of both the American College of Radiology and the American College of Chest Physicians, and is a member of the American Association for the Advancement of Science.
Q: From a clinical standpoint, what is the state of molecular imaging today and what technologies are used? What about the R &D pipeline?
A: Clinically, molecular imaging is almost entirely limited to nuclear medicine with both single photon and PET imaging. When one thinks of molecular imaging at this time, PET is the modality that is most widely considered a molecular imaging technique. FDG, the tracer that is most widely used clinically at this time, as well as new tracers that are being evaluated for looking at different biologic parameters of tumors, fall into the category of molecular imaging. There are some aspects of MRI that are being used today clinically and are considered molecular imaging, such as looking at oxygen metabolism.
From the research standpoint, molecular imaging technologies include SPECT, PET, MRI, magnetic resonance spectroscopy and ultrasound.
Q: How is molecular imaging going to change the way disease is currently diagnosed, treated and monitored?
A: It is going to have an increasingly important role. It is going to lead to earlier, more accurate diagnosis. And it's going to lead to earlier, more effective therapy. With some cancers and therapies, after one dose, PET can determine if the treatment is effective or not. Right now, for many of the cancer therapies, we are treating the patients for six weeks to three months with $50,000 to $100,000 worth of medication that frequently has side effects. We don't know until the end of that period whether that treatment is effective or not. Changing this is going to improve patient management tremendously. It will decrease healthcare costs, improve outcomes. And we can expect more progress in therapy monitoring, because what we are doing is the very tip of the iceberg.
Q: The projected molecular diagnostics market could reach $10 billion by 2007 (according to VisEn Medical). What will be the state of molecular imaging next year as well as in the next five and 10 years?
A: From a clinical standpoint, in the next year molecular imaging's not going to be a lot different than it is now.
In the future, I think a major use of molecular imaging is going to be similar to the way monoclonal antibody imaging is being used now, that is, as a precursor to monoclonal antibody therapy.
Molecular imaging will be used in the evaluation for the use of molecular therapies [the therapeutic agent will be radiolabeled as a diagnostic agent] to determine its distribution, localization and kinetics. Molecular imaging will be used as part of the pre-therapy analysis and following therapeutic effect. There will certainly be other ways to follow therapeutic effect by molecular imaging techniques. This is another big growth area that will be available by 2007. Ultrasound over the next five years will be complementary to molecular imaging, providing some anatomic information and potentially some flow information, but I don't see it having a direct impact on molecular imaging.
In 10 years, molecular imaging will be huge - almost all of imaging will be molecular imaging. It will be using a wide array of imaging techniques, some of which we may not even know of for sure yet. Some molecular imaging will be using SPECT and PET as it has progressed to by that time. Some molecular imaging will be using MRI or MR spectroscopy.