Although most clinical diagnostic imaging studies employ anatomic techniques such as computed tomography (CT) and magnetic resonance (MR) imaging, much of radiology research currently focuses on adapting these conventional methods to physiologic imaging as well as on introducing new techniques and probes for studying processes at the cellular and molecular levels in vivo, i.e. molecular imaging. Molecular imaging promises to provide new methods for the early detection of disease and support for personalized therapy. Although molecular imaging has been practiced in various incarnations for over 20 years in the context of nuclear medicine, other imaging modalities have only recently been applied to the noninvasive assessment of physiology and molecular events. Nevertheless, there has been sufficient experience with specifically targeted contrast agents and high-resolution techniques for MR imaging and other modalities that we must begin moving these new technologies from the laboratory to the clinic. This brief overview will outline molecular imaging from probe development to clinical translation, with a focus on translational (small animal) and early clinical imaging of cancer. We will discuss the ability for molecular imaging to assess specific signal transduction cascades, which are increasingly the targets of newer, cytostatic therapeutic agents, and provide examples of how existing or readily accessible molecular tracers and techniques can provide insight into rather complex biological phenomena in vivo.
- American Association for Cancer Research