Ga-68 DOTA-NOC Uptake in the Pancreas: Pathological and Physiological Patterns

OBJECTIVE:Gallium-68 (Ga-68) DOTA-1-NaI3-octreotide (DOTA-NOC) positron emission tomography (PET)/computed tomography (CT) is increasingly used for neuroendocrine tumors (NETs), often found primarily in the pancreas. However, physiologic uptake of DOTA-NOC has been described in the uncinate process of the pancreas. We studied DOTA-NOC uptake in this organ. MATERIALS AND METHODS:Ninety-six patients underwent 103 DOTA-NOC scans, with pathology-proven pancreatic NET (n = 40) and nonpancreatic NET or biochemical suspicion of NET (n = 63). RESULTS:DOTA-NOC uptake was detected in 35 documented pancreatic tumor sites (SUV5.5–165; mean25.7 ± 28.8; median17.8). Among 63 cases without previous known pathology, uptake was suspicious for tumor in 24 sites (SUV4.7–35; mean 16.3 ± 8.0; median14.1), and in 38 sites, it was judged as physiological, generally lower relative to adjacent structures (SUV2.2–12.6; mean6.6 ± 2.2; median6.2). In 24 scans with suspected tumor and in 37 of 38 scans with physiological uptake, diagnostic computed tomography or magnetic resonance imaging or endoscopic ultrasonography failed to detect tumor. CONCLUSIONS:Pancreatic DOTA-NOC uptake must be interpreted with caution, and further studies are required.