Nucl Med Mol Imaging.  2022 Feb;56(1):52-58. 10.1007/s13139-021-00723-5.

A Negative Correlation Between Blood Glucose Level and  ⁶⁸Ga‑DOTA‑TOC Uptake in the Pancreas Uncinate Process

• Oh D
• Choi H
• Paeng J
• Kang K
• Cheon G

• KMID: 2526705
• DOI: http://doi.org/10.1007/s13139-021-00723-5

Abstract

Purpose
⁶⁸Ga-DOTA-TOC uptake in the pancreas uncinate process is often found due to physiologic expression of somatostatin receptors (SSTR). We investigated the association of physiologic ⁶⁸Ga-DOTA-TOC uptake in the pancreas uncinate process with blood glucose level.
Methods
⁶⁸Ga-DOTA-TOC PET scans acquired from 44 patients (male:female = 20:24, age = 50.8 ± 14.8y [mean ± SD]) were retrospectively analyzed. The blood glucose level (BGL) was examined before ⁶⁸Ga-DOTA-TOC injection. Patients diagnosed with diabetes mellitus and patients with BGL over 200 mg/dl were excluded. ⁶⁸Ga-DOTA-TOC uptake was measured by the maximum standardized uptake values (SUVmax). Additionally, SSTR-positive volume (SV) in the pancreas uncinate process was measured with two different thresholds: by SUV cutoff of 2.5 ­(SV_2.5 ) and 40% of SUVmax ­(SV_40% ). These measurements on ⁶⁸Ga-DOTA-TOC PET were correlated with BGL.
Results
The mean of SUVmax of the pancreas uncinate process was 6.51 ± 2.04. ­SV_2.5 was 17.81 ± 7.14 ­cm³ , and ­SV_40% was 18.20 ± 8.83 ­cm³ . A significant negative correlation was found between SUVmax of the pancreas uncinate process and BGL (r = -0.37, p = 0.01). The ratio between SUVmax of the pancreas uncinate process and SUVmean of the pancreas body also showed a significance negative correlation with BGL (r = -0.40, p = 0.01). ­SV_2.5 (r = 0.27, p = 0.07) and ­SV_40% (r = -0.151, p = 0.32) were not significantly correlated with BGL.
Conclusion
Physiologic ⁶⁸Ga-DOTA-TOC uptake in the pancreas uncinate process was negatively correlated with BGL. Our results suggested that glycemia could affect physiologic uptake of ⁶⁸Ga-DOTA-TOC.

Keyword

⁶⁸Ga-DOTA-TOC; PET; Uncinate; Pancreatic polypeptide cell; Blood glucose level