Neuroendocrine Tumor Imaging With 68Ga-DOTA-NOC: Physiologic and Benign Variants

OBJECTIVE. Imaging with 68Ga-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)–octreotide analogs has become an important modality in patients with neuroendocrine tumors (NETs). In addition to high uptake in NET lesions, prominent physiologic radiotracer activity has been reported in the pituitary gland, pancreas, adrenal glands, liver, and spleen, and faint activity has been reported in the thyroid and gastrointestinal tract. This article describes previously unknown sites of 68Ga-DOTA–1-NaI3-octreotide (NOC) uptake unrelated to NETs. MATERIALS AND METHODS. One hundred eighty-two patients (96 female and 86 male patients; age range, 4–89 years) with documented (n = 156) or suspected (n = 26) NETs underwent 207 68Ga-DOTA-NOC PET/CT studies. Studies were retrospectively reviewed for the presence, intensity, and localization of foci of increased uptake that were further correlated with findings on additional imaging studies and clinical follow-up for a period of 4–32 months. RESULTS. Up...