PT - JOURNAL ARTICLE AU - Johannes Duell AU - Franziska Krummenast AU - Andreas Schirbel AU - Philipp Klassen AU - Samuel Samnick AU - Hilka Rauert-Wunderlich AU - Leo Rasche AU - Andreas K. Buck AU - Hans-Jürgen Wester AU - Andreas Rosenwald AU - Herrmann Einsele AU - Max S. Topp AU - Constantin Lapa AU - Malte Kircher TI - Improved Primary Staging of Marginal-Zone Lymphoma by Addition of CXCR4-Directed PET/CT AID - 10.2967/jnumed.120.257279 DP - 2021 Oct 01 TA - Journal of Nuclear Medicine PG - 1415--1421 VI - 62 IP - 10 4099 - http://jnm.snmjournals.org/content/62/10/1415.short 4100 - http://jnm.snmjournals.org/content/62/10/1415.full SO - J Nucl Med2021 Oct 01; 62 AB - PET/CT with 18F-FDG is an integral component in the primary staging of most lymphomas. However, its utility is limited in marginal-zone lymphoma (MZL) because of inconsistent 18F-FDG avidity. One diagnostic alternative could be the targeting of C-X-C motif chemokine receptor 4 (CXCR4), shown to be expressed by MZL cells. This study investigated the value of adding CXCR4-directed 68Ga-pentixafor PET/CT to conventional staging. Methods: Twenty-two newly diagnosed MZL patients were staged conventionally and with CXCR4 PET/CT. Lesions identified exclusively by CXCR4 PET/CT were biopsied as the standard of reference and compared with imaging results. The impact of CXCR4-directed imaging on staging results and treatment protocol was assessed. Results: CXCR4 PET/CT correctly identified all patients with viable MZL and was superior to conventional staging (P < 0.001). CXCR4-directed imaging results were validated by confirmation of MZL in 16 of 18 PET-guided biopsy samples. Inclusion of CXCR4 PET/CT in primary staging significantly impacted staging results in almost half of patients and treatment protocols in a third (upstaging, n = 7; downstaging, n = 3; treatment change, n = 8; P < 0.03). Conclusion: CXCR4 PET/CT is a suitable tool in primary staging of MZL and holds the potential to improve existing diagnostic algorithms.