⁶⁸Ga DOTA TATE PET/CT in patients with neuroendocrine tumors: a technologist’s perspective

Objectives Many neuroendocrine tumors (NET) strongly express somatostatin receptors. Taking advantage of this characteristic, several radiotracers have been developed to evaluate NET. Traditionally, In-111 Octreoscan^® has been used for scanning patients with NET. However, In-111 Octreoscan^® has known limitations. F-18 FDG PET/CT can provide additional complementary information in selected NET cases. Ga-68 DOTA-TATE has become increasingly popular as a molecular tool for imaging NET.

Methods Ga-68 DOTA-TATE PET/CT scans were done in NET patients under an IRB-approved research protocol. Every patient first signed an informed consented. Vital signs including oxygen saturation levels, respiratory rate, and blood pressure were recorded prior to injection of the tracer and at the completion of the scan. A dose of 5-7 mCi Ga-68 DOTA-TATE was administered intravenously. After a 45-60 minute delay, PET/CT was performed from vertex to mid-thighs.

Results 70 patients (34 men, 36 women), 31-68 year-old (mean±SD: 57.5±13.1) were scanned after injections of 3.9-6.9 mCi (mean±SD: 5.8±0.7) of Ga-68 DOTA-TATE. GE Discovery 600 PET/CT scanner was used in 39 cases and Discovery 690 in 31 cases. The wait time from injection of the radiopharmaceutical to start of the scan was 44-80 minutes (mean±SD: 57.6±6.5). The duration of the scan ranged 18-45 minutes (mean±SD: 26.7±7.2). All PET images had diagnostic quality. Vital signs were stable in all patients and no adverse events were recorded.

Conclusions Ga-68 DOTA-TATE provides diagnostic images of high quality in patients with NET, without adverse events. The short duration of the exam leads to improved patient convenience and is a significant advantage over the standard of care (in the U.S.) In-111 Octreoscan^®.

Research Support None