ABSTRACT
Functional imaging with positron emission tomography (PET) has recently taken on an increasingly important role in the management of patients with cancer, reflecting a growing need to evaluate disease status, not only at the time of diagnosis and staging, but also at regular intervals during follow-up. In most countries of the world, PET imaging has limited availability, and close liaison between cancer clinicians and imagers is essential if optimum utilization is to be achieved. As with all imaging techniques the choice of PET as an option is dependent on many factors, which include the information being sought, the availability and the accuracy of PET imaging, and local expertise. At a time of increasing demand for imaging resources and increasing health-care costs, economic factors increasingly influence decisions regarding the usage of PET in a given clinical situation. PET creates tomographic images that represent metabolic activity of underlying tissue processes. Major developments that have enabled the successful clinical implementation of this technique include radiopharmaceuticals that resemble endogenous biological compounds, quantification of tracer distribution, volume data acquisition, whole-body tomographic imaging, and most recently simultaneously acquired CT data. This chapter cannot adequately cover these areas, and readers are invited to review the many specialist texts that cover the areas of hardware, tracers, provide organ-by-organ reviews, and discuss economic considerations. Instead, we intend to review 18F-fluoro-2-deoxy-D-glucose [18FDG] PET from the standpoint of clinical usage evaluating its use for diagnosing cancer, for staging patients with cancer, for prognostication, to evaluate residual disease, and to detect recurrence. For the sake of brevity, each of these themes will be discussed in greater depth for one or two of the commonest cancers to provide readers with an idea on the principles of 18FDG PET use in clinical practice.
