Dosimetry and optimal scan time of 18FSiTATE-PET/CT in patients with neuroendocrine tumours

Beyer, Leonie; Gosewisch, Astrid; Lindner, Simon; Völter, Friederike; Mittlmeier, Lena M.; Tiling, Reinhold; Brendel, Matthias; Cyran, Clemens C.; Unterrainer, Marcus; Rübenthaler, Johannes; Auernhammer, Christoph J.; Spitzweg, Christine; Böning, Guido; Gildehaus, F. J.; Jurkschat, Klaus; Wängler, Carmen; Wängler, Björn; Schirrmacher, Ralf; Wenter, Vera; Todica, Andrei; Bartenstein, Peter und Ilhan, Harun (2021): Dosimetry and optimal scan time of 18FSiTATE-PET/CT in patients with neuroendocrine tumours. In: European journal of nuclear medicine and molecular imaging, Bd. 48: S. 3571-3581

Abstract

PURPOSE Radiolabelled somatostatin analogues targeting somatostatin receptors (SSR) are well established for combined positron emission tomography/computer tomography (PET/CT) imaging of neuroendocrine tumours (NET). 18FSiTATE has recently been introduced showing high image quality, promising clinical performance and improved logistics compared to the clinical reference standard 68Ga-DOTA-TOC. Here we present the first dosimetry and optimal scan time analysis. METHODS Eight NET patients received a 18FSiTATE-PET/CT (250 ± 66~MBq) with repeated emission scans (10, 30, 60, 120, 180~min after injection). Biodistribution in normal organs and SSR-positive tumour uptake were assessed. Dosimetry estimates for risk organs were determined using a combined linear-monoexponential model, and by applying 18F S-values and reference target masses for the ICRP89 adult male or female (OLINDA 2.0). Tumour-to-background ratios were compared quantitatively and visually between different scan times. RESULTS After 1 h, normal organs showed similar tracer uptake with only negligible changes until 3 h post-injection. In contrast, tracer uptake by tumours increased progressively for almost all types of metastases, thus increasing tumour-to-background ratios over time. Dosimetry resulted in a total effective dose of 0.015 ± 0.004~mSv/MBq. Visual evaluation revealed no clinically relevant discrepancies between later scan times, but image quality was rated highest in 60 and 120~min images. CONCLUSION 18FSiTATE-PET/CT in NET shows overall high tumour-to-background ratios from 60 to 180~min after injection and an effective dose comparable to 68Ga-labelled alternatives. For clinical use of 18FSiTATE, the best compromise between image quality and tumour-to-background contrast is reached at 120~min, followed by 60~min after injection.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Sprache: Englisch