Results of 68Gallium-DOTATATE PET/CT Scanning in Patients with Multiple Endocrine Neoplasia Type 1

Background Screening for neuroendocrine tumors (NETs) in patients with multiple endocrine neoplasia type 1 (MEN1) is recommended to detect primary and metastatic tumors, which can result in significant morbidity and mortality. The utility of somatostatin receptor imaging 68 Gallium-DOTATATE PET/CT in patients with MEN1 is not known. The aim of this study was to prospectively determine the accuracy of 68 Gallium-DOTATATE PET/CT vs 111 In- pentetreotide single-photon emission CT (SPECT)/CT and anatomic imaging in patients with MEN1. Study Design We performed a prospective study comparing 68 Gallium-DOTATATE PET/CT, 111 In-pentetreotide SPECT/CT, and triphasic CT scan to clinical, biochemical, and pathologic data in 26 patients with MEN1. Results 68 Gallium-DOTATATE PET/CT detected 107 lesions; 111 In-pentetreotide SPECT/CT detected 33 lesions; and CT scan detected 48 lesions. Lesions detected on 68 Gallium-DOTATATE PET/CT had high standard uptake value (SUV) max (median SUV max = 72.8 [range 19 to 191]). In 7 of the 26 patients (27%), 68 Gallium-DOTATATE PET/CT was positive, with a negative 111 In-pentetreotide SPECT/CT, and in 10 patients (38.5%), additional metastases were detected (range 0.3 cm to 1.5 cm). In 8 of the 26 patients (31%), there was a change in management recommendations as a result of the findings on 68 Gallium-DOTATATE PET/CT that were not seen on 111 In-pentetreotide SPECT/CT and CT scan. Conclusions 68 Gallium-DOTATATE PET/CT is more sensitive for detecting NETs than 111 In-pentetreotide SPECT/CT and CT scan in patients with MEN1. This imaging technique should be integrated into radiologic screening and surveillance of patients with MEN1 because it can significantly alter management recommendations.