Scar sarcoidosis: A rare entity found by 18F-FDG-PET/CT

Abstract 18 F-labeled fluoro-2-positron deoxyglucose emission tomography/computed tomography has been widely used in malignancy assessment, however, is not tumor-specific and may be taken up by non-malignant conditions such as sarcoidosis. Sarcoidosis is a systemic inflammatory disorder and scar sarcoidosis is a rare manifestation of the disease. A 60-year-old man with a past medical history of synchronous colon adenocarcinoma and clear cell renal cell carcinoma with clinical suspicion of tumor recurrence. 18 F-labeled fluoro-2-positron deoxyglucose emission tomography/computed tomography scan demonstrated lesions with increased fluorodeoxyglucose uptake in mediastinal and left supraclavicular lymph nodes, along with hypermetabolic cutaneous foci that corresponded with previous surgical scars. Skin biopsy was suggestive of sarcoidosis.