Head-to-head comparison of [18F]AlF-NOTA-JR11 PET/MR and [68Ga]Ga-DOTA-TATE PET/CT in patients with neuroendocrine tumors.

PURPOSE: To compare [18F] AlF-NOTA-JR11 PET/MR and [68Ga]Ga-DOTA-TATE PET/CT in patients with neuroendocrine tumors (NETs). METHODS: Forty-one patients with biopsy-proven NETs were enrolled and underwent [68Ga]Ga-DOTA-TATE PET/CT and [18F] AlF-NOTA-JR11 PET/MR. Physiological organ uptake, lesion number, maximum standardized uptake value (SUVmax) and tumor-to-background ratio (TBR) were compared between the two examinations. RESULTS: [18F] AlF-NOTA-JR11 PET/MR and [68Ga]Ga-DOTA-TATE PET/CT depicted 924 and 580 lesions, respectively (p < 0.001).These included 754 and 405 liver metastases(p < 0.001), as well as 29 and 25 primary tumors (p = 0.125), respectively. The 405 liver metastases detected by both examinations were significantly larger than the 349 lesions detected only by [18F]AlF-NOTA-JR11 [median diameter, 14.00 mm (Q1, Q3: 10.00, 21,00) vs. 6.00 mm (Q1, Q3: 5.00, 9.00); p < 0.001]. No significant differences were found for the detection of lymph node metastases (p = 1.000) or bone metastases (p = 0.188). In the patient-based comparison, 76% of patients (31/41) had more lesions detected by [18F]AlF-NOTA-JR11 PET/MR than by [68Ga]Ga-DOTA-TATE PET/CT. Lesion SUVmax for [18F]AlF-NOTA-JR11 was significantly lower than that for [68Ga]Ga-DOTA-TATE in primary tumors (p = 0.002), liver metastases (p = 0.017) and bone metastases (p = 0.008), whereas no significant difference was observed in lymph node metastases (p = 0.144). [18F]AlF-NOTA-JR11 PET/MR showed higher TBR than [68Ga]Ga-DOTA-TATE PET/CT in primary tumors (p = 0.014), lymph node metastases (p = 0.034) and liver metastases (p < 0.001), with no significant difference in bone metastases(p = 0.343). CONCLUSION: [18F]AlF-NOTA-JR11 PET/MR shows lower background uptake and higher TBR for primary tumors, lymph node metastases and liver metastases. It also detected more liver metastases than [68Ga]Ga-DOTA-TATE PET/CT. These findings provide valuable evidence supporting the clinical use of [18F]AlF-NOTA-JR11 PET/MR in patients with NETs. TRIAL REGISTRATION NUMBER: 2020KT15 DATE OF REGISTRATION: 30/03/2020.