Imaging studies including plain X-ray and a computed tomography (CT) scan of the shoulder were negative, and a nuclear scan was negative for any uptake.
MRI of the left shoulder joint with and without contrast (left) was performed, revealing multiple enhancing lesions in the glenoid and the medial aspect of the metaphysis of the left humerus. Bone scans revealed symmetric increased radiotracer uptake in both shoulders, hips and knees.
FDG-Positron emission tomography (PET) scans showed uptake in the lymph nodes involving the hila, mediastinum and retroperitoneum, along with diffusely increased uptake of the left hepatic lobe. Multiple foci of increased FDG uptake involving both axial and proximal appendicular skeleton were seen as well, consistent with either sarcoidosis or lymphoma.
What diagnosis do you suspect for this finding on FDG-PET? Which further tests would you order?
See the diagnosis, images, and discussion.