ABSTRACT
Sixty two years old man referred to our clinic due to suspicion of thymic mass. The hypermetabolic nodular lesion in the right lung upper lobe was seen in 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) in addition to the mass in the anterior mediastinum which was found to without malignancy. The patient underwent wedge resection and final diagnosis was pulmonary giant cell carcinoma. In follow-up 18F-FDG PET/CT multiple lesions with pathological activity were observed in the cerebrum, right postauricular region, bilateral adrenal, stomach, pancreas, pelvic soft tissue, mesenteric, left femur and bilateral lung parenchyma 6 months after. The pathology results of the right frontal, pelvic mass and the postauricular region were metastasis.