RT Journal Article SR Electronic T1 Imaging of C-X-C Motif Chemokine Receptor 4 Expression in 690 Patients with Solid or Hematologic Neoplasms Using 68Ga-Pentixafor PET JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1687 OP 1692 DO 10.2967/jnumed.121.263693 VO 63 IS 11 A1 Andreas K. Buck A1 Alexander Haug A1 Niklas Dreher A1 Alessandro Lambertini A1 Takahiro Higuchi A1 Constantin Lapa A1 Alexander Weich A1 Martin G. Pomper A1 Hans-Jürgen Wester A1 Anja Zehndner A1 Andreas Schirbel A1 Samuel Samnick A1 Marcus Hacker A1 Verena Pichler A1 Stefanie Hahner A1 Martin Fassnacht A1 Hermann Einsele A1 Sebastian E. Serfling A1 Rudolf A. Werner YR 2022 UL http://jnm.snmjournals.org/content/63/11/1687.abstract AB In recent years, molecular imaging addressing the C-X-C motif chemokine receptor 4 (CXCR4) has increasingly been used in various clinical settings. Here, we aimed to assess radiopharmaceutical uptake and image contrast to determine the most relevant clinical applications for CXCR4-directed imaging. We also investigated the impact of specific activity on scan contrast. Methods: Patients (n = 690) with a variety of neoplasms underwent a total of 777 PET/CT scans with 68Ga-Pentixafor, serving as the CXCR4-specific radioligand. A semiquantitative target lesion analysis was conducted (providing SUVmax and target-to-blood pool ratio [TBR], defined as SUVmax [from target lesion] divided by SUVmean [from blood pool]). The applied specific activity (in MBq/μg) was compared with semiquantitative assessments. Results: Of the 777 scans, 242 did not show discernible uptake in disease sites, leaving 535 PET scans (68.9%) for further analysis. Very high tracer uptake (SUVmax > 12) was found in multiple myeloma (n = 113), followed by adrenocortical carcinoma (n = 30), mantle cell lymphoma (n = 20), adrenocortical adenoma (n = 6), and small cell lung cancer (n = 12). Providing information on image contrast, comparable results for TBR were recorded, with TBR (>8) in multiple myeloma, mantle cell lymphoma, and acute lymphoblastoid leukemia (n = 6). When comparing specific activity with semiquantitative parameters, no significant correlation was found for SUVmax or TBR (P ≥ 0.612). Conclusion: In this large cohort, 68Ga-Pentixafor demonstrated high image contrast in a variety of neoplasms, particularly for hematologic malignancies, small cell lung cancer, and adrenocortical neoplasms. The present analysis may provide a roadmap for detecting patients who may benefit from CXCR4-targeted therapies.