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What does FDG activity indicate in an incidental thyroid nodule? Does this need a biopsy?
FDG activity in an incidental thyroid nodule is a concerning finding since it is correlated with thyroid malignancy. The nodule needs an ultrasound evaluation before biopsy, but will probably warrant biopsy regardless of what the ultrasound shows.
On the initial CT study, a 6 mm hypoattenuating non-calcified thyroid nodule was noted (red arrow). It was not followed up with a thyroid ultrasound.
On the follow-up PET-CT, in addition to evaluating the SUV of the lung mass, the incidental thyroid nodule demonstrated FDG uptake.