PET-CT indications

Dr Dan J Bell and Dr Ki Yap et al.

PET-CT is a combination of cross-sectional anatomic information provided by CT and the metabolic information provided by positron emission tomography (PET).

PET is most commonly performed with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG). Fluorine-18 (F-18) is an unstable radioisotope and has a half-life of approximately 110 minutes.

The indications for F-18 fluorodeoxyglucose (FDG) PET-CT imaging include:

  • staging of cancer which potentially can be treated radically (e.g. small cell lung cancer)
  • establish baseline staging before commencing treatment (e.g. GIST)
  • evaluation of an indeterminate lesion (solitary pulmonary nodule)
  • assessing response to therapy
  • evaluation of suspected disease recurrence, relapse and/or residual disease (e.g. lymphoma, testicular seminoma)
  • to guide a biopsy (e.g. pleural biopsy for mesothelioma)

PET-CT can also be used as a problem-solving tool:

  • occult primary lesion (e.g. non-metastatic manifestation of neoplastic disease)
  • evaluation of suspected recurrence in patients with equivocal conventional imaging
  • evaluation of residual disease in patients with treated differentiated thyroid carcinoma and treated medullary thyroid carcinoma with negative/equivocal conventional imaging
  • prior to radical nodal resection in patients with metastatic melanoma
  • suspected malignant transformation in plexiform neurofibromata (neurofibromatosis type 1)
  • differentiate between radiation-induced necrosis and tumour recurrence (e.g. primary CNS malignancy)
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Article information

rID: 14457
Section: Gamuts
Synonyms or Alternate Spellings:
  • Indications for PET/CT imaging
  • Indications for PETCT imaging
  • PET-CT indications
  • Indications for PET-CT imaging
  • Indications for PET-CT

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