Exploration of the Feasibility of One-day Dual-low-activity 68Ga-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms

Purpose The standard 2-day dual-tracer PET protocol provides more information but is time consuming. Thus, this study aimed to validate the feasibility of 1-day ⁶⁸ Ga-DOTATATE and ¹⁸ F-FDG dual-low-activity PET/MR imaging in patient with neuroendocrine neoplasms (NENs). Procedures: Fourteen pairs of NENs patients who underwent 1-day ⁶⁸ Ga-DOTATATE and ¹⁸ F-FDG dual-low-activity PET/MR and 2-day ⁶⁸ Ga-DOTATATE and ¹⁸ F-FDG PET/MR were retrospectively enrolled. Imaging analysis was performed, including lesion detection rate and diagnostic confidence. Additionally, the diagnostic confidence was also assessed based on ⁶⁸ Ga-DOTATATE PET, ¹⁸ F-FDG PET and PET/MR, respectively. Results The 1-day protocol detected 39 out of 40 lesions in 14 patients, while the 2-day protocol detected 67 out of 68 lesions in 14 patients. No significant differences were observed in lesion detection (all P > 0.05). There was no significant difference in diagnostic confidence between the 1-day protocol and the 2-day protocol for ⁶⁸ Ga-DOTATATE PET (median [IQR]: 3[2–3] vs. 3[2–3]), ¹⁸ F-FDG PET (1[1–2] vs. 1[1–1]), and PET/MR (4[3–5] vs. 5[4–5]) in all lesions (all P > 0.05). Conclusion the 1-day ⁶⁸ Ga-DOTATATE and ¹⁸ F-FDG dual-low-activity PET/MR imaging protocol in patients with NENs is feasible and provides equivalent lesion detection and diagnostic confidence compared to the 2-day protocol.