Ga-68 DOTA-NOC uptake in the pancreas: pathological and physiological patterns.

ABSTRACT

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 (SUV 5.5-165; mean 25.7 ± 28.8; median 17.8). Among 63 cases without previous known pathology, uptake was suspicious for tumor in 24 sites (SUV 4.7-35; mean 16.3 ± 8.0; median 14.1), and in 38 sites, it was judged as physiological, generally lower relative to adjacent structures (SUV 2.2-12.6; mean 6.6 ± 2.2; median 6.2). 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.