Chloé Merino, Camille Sergeant, Alexandre Vasiljevic, Emmanuel Jouanneau, Gérald Raverot, Anthime Flaus
We report a rare pituitary imaging pitfall on 18F-FET PET/CT in a 38-year-old man with a history of treated pulmonary sarcoidosis. MRIs demonstrated a left-sided pituitary neuroendocrine tumor (PitNET)/pituitary adenoma. 18F-FET PET/CT showed discordant bilateral uptake with higher activity on the right side. Histopathological analysis demonstrated a PitNET of corticotroph type on the left side and noncaseating granulomas consistent with sarcoidosis on the right side. Neurosarcoidosis should be considered a potential cause of false-positive 18F-FET uptake.