False-Positive Skin Uptake on 18F-Choline PET/CT Related to an Inflammatory Epidermoid Cyst in a Patient With Parathyroid Adenoma

A 70-year-old man with primary hyperparathyroidism underwent 18F-choline PET/CT to localize a parathyroid adenoma before surgery. 18F-choline PET/CT confirmed the right superior parathyroid adenoma but also revealed skin uptake corresponding to an inflammatory epidermoid cyst of the left neck. Two months later, the patient underwent successful minimally invasive parathyroidectomy. The epidermoid cyst was also excised. Inflammatory epidermoid cysts can be a cause of false-positive 18F-choline skin uptake.