18F-FDG PET Detection of a Medullary Thyroid Carcinoma in a Patient With SMZL.

Incidental thyroid FDG uptake is not rarely encountered on PET studies. In this case, we present an incidental thyroid focus of F-FDG uptake identified in a patient with splenic marginal zone lymphoma during the baseline and the response assessment PET/CT study that proved to be medullary thyroid carcinoma on subsequent histological examination.