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  • Review Article
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Technology Insight: advances in molecular imaging and an appraisal of PET/CT scanning

Abstract

PET/CT imaging has rapidly emerged as an important imaging tool in oncology. The success of PET/CT imaging is based on several features. First, patients benefit from a comprehensive diagnostic anatomical and functional (molecular) whole-body survey in a single session. Second, PET/CT provides more-accurate diagnostic information than PET or CT alone. Third, PET/CT imaging allows radiation oncologists to use the functional information provided by PET scans for radiation treatment planning. In this Review we discuss the technical features of PET/CT, its economic aspects within the health-care system, and its role in diagnosis, staging, restaging and treatment monitoring as well as radiation planning in patients with cancer.

Key Points

  • PET/CT with the glucose analog [18F]fluorodeoxyglucose has emerged as an important tool for staging and restaging a variety of malignant tumors

  • PET/CT has been shown to be more accurate for detection of metastatic lesions than either PET or CT alone

  • By providing functional and morphological information in a single examination, PET/CT can shorten the diagnostic workup of cancer patients

  • PET/CT allows the functional information of PET to be used for radiation treatment planning purposes

  • PET/CT will facilitate the clinical use of new molecular imaging probes by showing the exact anatomical localization of their distribution in normal organs and in tumors

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Figure 1: Number of PET/CT and PET scans performed in the US per year from 2000 to 2006, with an estimate (*) for 2007.
Figure 2: PET/CT study in a patient with non-small-cell lung cancer.
Figure 3: Metabolically active brown adipose tissue in a patient with a history of Hodgkin's disease.
Figure 4: Impact of PET/CT on radiation treatment planning.

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Correspondence to Wolfgang A Weber.

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Weber, W., Grosu, A. & Czernin, J. Technology Insight: advances in molecular imaging and an appraisal of PET/CT scanning. Nat Rev Clin Oncol 5, 160–170 (2008). https://doi.org/10.1038/ncponc1041

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