Thymic Granuloma Mimicking Malignancy on 18F-FDG PET/CT.

We present a case with an unexpected nodule in the thymus showing increased F-FDG uptake on PET/CT. The nodule was surgically removed. Histopathologic examination revealed granuloma in the thymus. This case indicates physicians and radiologists must be aware that although thymic granuloma is rare, it should be included in the differential diagnosis of the thymic lesions with F-FDG accumulation along with neoplastic and nonneoplastic conditions.