Incidental thyroid uptake on PET scanning: epidemiology, clinical significance, and management challenge

Abstract

Incidental lesions of the thyroid are increasingly discovered as the prevalence of medical imaging escalates. The likelihood of malignancy must be assessed for each of these incidentalomas. The utility of the metabolic data derived from the identification of these lesions on PET/CT imaging is unclear. The overall rate of detection of thyroid incidentalomas on PET/CT is estimated at 1.5%-4.2%. However, this rate varies by the pattern of uptake. Several studies have evaluated predictive measures such as maximal standardized uptake value (SUV_max) and radiomics. However, no definitive conclusion has been reached. Given that the majority of PET/CT scans are performed in the context of malignancy, we recommend first assessing the general condition and life expectancy of patients when PET-detected thyroid incidentalomas are unveiled. We also recommend considering observation versus diagnostic workup with further imaging and/or fine-needle aspiration and cytology.

Keywords

PEToma / PET-detected thyroid incidentaloma / PET-associated incidental neoplasm

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