PT - JOURNAL ARTICLE AU - Rohini Sharma AU - Kumar G. Kallur AU - Jin S. Ryu AU - Ramanathapuram V. Parameswaran AU - Henrik Lindman AU - Norbert Avril AU - Fergus V. Gleeson AU - Jong D. Lee AU - Kyung-Han Lee AU - Michael J. O’Doherty AU - Ashley M. Groves AU - Matthew P. Miller AU - Edward J. Somer AU - Charles R. Coombes AU - Eric O. Aboagye TI - Multicenter Reproducibility of <sup>18</sup>F-Fluciclatide PET Imaging in Subjects with Solid Tumors AID - 10.2967/jnumed.115.158253 DP - 2015 Dec 01 TA - Journal of Nuclear Medicine PG - 1855--1861 VI - 56 IP - 12 4099 - http://jnm.snmjournals.org/content/56/12/1855.short 4100 - http://jnm.snmjournals.org/content/56/12/1855.full SO - J Nucl Med2015 Dec 01; 56 AB - Integrins are upregulated on both tumor cells and associated vasculature, where they play an important role in angiogenesis and metastasis. Fluciclatide is an arginine-glycine-aspartic acid peptide with high affinity for αvβ3/αvβ5 integrin, which can be radiolabeled for PET imaging of angiogenesis. Thus, 18F-fluciclatide is a potential biomarker of therapeutic response to antiangiogenic inhibitors. The aim of this study was to evaluate the reproducibility of 18F-fluciclatide in multiple solid-tumor types. Methods: Thirty-nine patients underwent PET/CT scanning at 40, 65, and 90 min after injection of 18F-fluciclatide (maximum, 370 MBq) on 2 separate days (2–9 d apart). Patients did not receive any therapy between PET/CT scans. 18F-fluciclatide images were reported and quantitative measures of uptake were extracted using the PERCIST methodology. Intrasubject reproducibility of PET uptake in all measurable lesions was evaluated by calculating relative differences in SUV between PET scans for each lesion during the 2 imaging sessions. Results: Thirty-nine measurable lesions were detected in 26 patients. Lesion uptake correlated strongly across imaging sessions (r = 0.92, P &lt; 0.05, at 40 min; r = 0.94, P &lt; 0.05, at 65 min; r = 0.94, P &lt; 0.05, at 90 min) with a mean relative difference and SD of the relative difference of 0.006 ± 0.18 at 40 min, 0.003 ± 0.19 at 65 min, and 0.025 ± 0.20 at 90 min. This reflects 95% limits of repeatability of 35%–39% for the difference between the 2 SUV measurements or a variability of 18%–20% in agreement from that observed in well-calibrated multicenter 18F-FDG studies. Conclusion: The test–retest reproducibility of 18F-fluciclatide across multiple tumor types has been measured and shown to be acceptable. This is an important step in the development of this in vivo biomarker to identify and quantify response to antiangiogenic therapy in cancer patients.