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Everolimus and peptide receptor radionuclide therapy (PRRT, 177 Lu-DOTATATE) are 2 treatments recommended in guidelines for gastroenteropancreatic metastatic neuroendocrine tumors. However, the best treatment sequence remains unknown. Methods: We designed a retrospective multicenter study that included patients from the national prospective database of the Groupe d'Étude des Tumeurs Endocrines who had been treated using everolimus and PRRT between April 2004 and October 2022. The primary aim was to compare the 2 treatments (everolimus and PRRT) in terms of efficacy and safety, and the secondary aim was to evaluate the sequences (PRRT followed by everolimus or everolimus followed by PRRT) based on overall progression-free survival (PFS) (PFS during first treatment + PFS during second treatment) in patients with metastatic neuroendocrine tumors. Results: Both treatments were used for 84 patients. The objective response rate and median PFS were 5 (6.0%) and 16.1 mo (95% CI, 11.5-20.7 mo), respectively, under everolimus and 19 (22.6%) and 24.5 mo (95% CI, 17.7-31.3 mo), respectively, for PRRT. The safety profile was also better for PRRT. Median overall PFS was 43.2 mo (95% CI, 33.7-52.7 mo) for the everolimus-PRRT sequence and 30.6 mo (95% CI, 17.8-43.4 mo) for the PRRT-everolimus sequence (hazard ratio, 0.69; 95% CI, 0.39-1.24; P = 0.22). Conclusion: PRRT was more effective and less toxic than everolimus. Overall PFS was similar between the 2 sequences, suggesting case-by-case discussion if the patient is eligible for both treatments, but PRRT should be used first when an objective response is needed or in frail populations., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Our objective was to compare the respective value of 68 Ga-DOTATOC and 18 F-DOPA PET/CT for initial staging or presurgical work-up of patients with small-intestine neuroendocrine tumors (SiNETs). Methods: This was a retrospective, multicenter, noninterventional investigation involving 53 non-surgically treated SiNET patients who underwent both 68 Ga-DOTATOC and 18 F-DOPA PET/CT within a 6-mo interval without surgical intervention or therapeutic change between the 2 PET/CT studies. Percentage detection rate was calculated according to per-region and per-lesion analyses. Sensitivity for primary tumor detection was assessed in 37 surgically treated patients, taking surgical results (76 SiNETs) as the diagnostic gold standard. Results: 68 Ga-DOTATOC PET/CT and 18 F-DOPA PET/CT individually identified at least 1 primary SiNET in 92% (34/37) of the patients. Intestinal tumor multifocality was confirmed by histology in 8 patients. 68 Ga-DOTATOC and 18 F-DOPA PET/CT were concordantly positive for tumor multifocality in 5 patients, discordantly positive in 2 patients, and concordantly negative in 1 patient. The detection rate for subdiaphragmatic nodal metastases on per-region-based analysis was 91% and 98% for 68 Ga-DOTATOC and 18 F-DOPA PET/CT, respectively ( P = 0.18). 18 F-DOPA PET/CT detected a higher number of abnormal subdiaphragmatic nodes ( P = 0.009). Regarding mesenteric nodes only, 18 F-DOPA PET/CT detected more positive regions ( P = 0.005) and nodal lesions ( P = 0.003) than 68 Ga-DOTATOC PET/CT, including nodes at the origin of mesenteric vessels. For detection of distant metastases, 68 Ga-DOTATOC and 18 F-DOPA PET/CT performed equally well on a per-region-based analysis. As compared with 68 Ga-DOTATOC, 18 F-DOPA PET/CT detected more hepatic ( P < 0.001), peritoneal ( P < 0.001), and lung metastases ( P < 0.001). Conclusion: 18 F-DOPA PET/CT detected more lesions than 68 Ga-DOTATOC PET/CT in the studied patients. The respective roles of the two should be discussed in terms of disease staging and treatment selection., (© 2022 by the Society of Nuclear Medicine and Molecular Imaging.)