Evaluation of 18F-AlF-NOTA-octreotide for imaging neuroendocrine neoplasms: comparison with 68Ga-DOTATATE PET/CT

Abstract

Objective To evaluate the diagnostic efficacy of 18F-AlF-NOTA-octreotide (18F-OC) PET/CT compared with that of 68Ga-DOTATATE PET/CT. Materials and methods Twenty patients (mean age: 52.65 years, range: 24–70 years) with biopsy-proven neuroendocrine neoplasms (NENs) were enrolled in this prospective study. We compared the biodistribution profiles in normal organs based on the maximum standard uptake value (SUVmax) and mean standard uptake value (SUVmean), and uptake in NEN lesions by measuring the SUVmax on 18F-OC and 68Ga-DOTATATE PET/CT images. The tumor-to-liver ratio (TLR) and tumor-to-spleen ratio were calculated by dividing the SUVmax of different tumor lesions by the SUVmean of the liver and spleen, respectively. The Wilcoxon signed-rank test was used to compare nonparametric data. Data were expressed as the median (interquartile range). Results In most organs, there were no significant differences in the biodistribution of 68Ga-DOTATATE and 18F-OC. 18F-OC had significantly lower uptake in the salivary glands and liver than 68Ga-DOTATATE. 18F-OC detected more lesions than 68Ga-DOTATATE. The uptake of 18F-OC in the tumors was higher in most patients, but the difference was not statistically significant relative to that of 68Ga-DOTATATE. However, the TLRs of 18F-OC were higher in most patients, including for lesions in the liver (p = 0.02) and lymph nodes (p = 0.02). Conclusion Relative to 68Ga-DOTATATE, 18F-OC possesses favorable characteristics with similar image quality and satisfactory NEN lesion detection rates, especially in the liver due to its low background uptake. 18F-OC therefore offers a promising clinical alternative for 68Ga-DOTATATE.

18F-AlF-NOTA-Octreotide Outperforms68Ga-DOTATATE/NOC PET in Neuroendocrine Tumor Patients: Results from a Prospective, Multicenter Study

“…In accordance with Hou et al (8), we observed considerable variability in lesion uptake both between and within patients. Differences in SSTR affinity profile between 18 F-AlF-OC and 68 Ga-DOTATATE/NOCto our knowledge, the exact affinity profile for 18 F-AlF-OC is still unknown in combination with NET heterogeneity may lie at the basis of this finding.…”

“…Nevertheless, higher TBR values for 18 F-AlF-OC are mainly explained by significantly lower background uptake. In particular, the lower background uptake with 18 F-AlF-OC in the liver significantly improves detection of liver metastases as reflected by the high DDR value of 33.1% (95% CI: 21.7%-44.4%), which is consistent with previous observations (5,8). Tracer clearance may partly explain the lower background values for 18 F-AlF-OC, as 18 F-AlF-OC imaging was done at a later time point (2h p.i.)…”

“…Routine and study scans were randomized per group of 20 patients (40 scans per group) and information regarding patient and radiopharmaceutical was removed from the DICOM headers. Furthermore, since normal salivary gland uptake is markedly higher with 68 Ga-DOTATATE compared with 18 F-AlF-OC (5,8), all PET datasets were trimmed by an independent operator to remove the head region. A positive lesion was defined as a volume of increased tracer uptake compared to background, deemed to be caused by the presence of NET cells, and that is unlikely to be attributed to physiological or benign etiology (e.g.…”

“…Two independently performed first clinical translations of 18 F-AlF-OC in healthy volunteers and NET patients have reported favorable dosimetry, biodistribution, tracer kinetics and lesion targeting (4,5). First comparisons of 18 F-AlF-OC with 68 Ga-DOTATATE in two small NET patient groups (n = 6 and n = 20) have shown similar lesion detection rates and tumor uptake (5,8). However, a thorough head-to-head comparison with 68 Ga-DOTA-SSA PET in large patient groups is still lacking.…”

Primary Neuroendocrine Carcinoma of Pineal Gland With Extensive Meningeal Metastasis Detected by 18F-NOTATATE PET/CT

“…1,9,10 Several studies have shown that its detection rate of NET is highly consistent with that of 68 Ga-DOTATATE, which can be used for clinical staging. [10][11][12][13] Previous studies have shown that 18 F-NOTATATE is better than 18 F-FDG for imaging well-differentiated NET, whereas 18 F-FDG is better for imaging poorly differentiated NET. 1 However, this case is a poorly differentiated NEC, with marked 18 F-NOTATATE expression and equivocal FDG uptake.…”