RT Journal Article SR Electronic T1 Detection efficacy of 18F-rhPSMA-7.3 PET/CT and impact on patient management in patients with biochemical recurrence of prostate cancer after radical prostatectomy and prior to potential salvage treatment JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP jnumed.120.260091 DO 10.2967/jnumed.120.260091 A1 Isabel Rauscher A1 Amir Karimzadeh A1 Kilian Schiller A1 Thomas Horn A1 Calogero D'Alessandria A1 Charlott Franz A1 Hannah Wörther A1 Noemi Nguyen A1 Stephanie E Combs A1 Wolfgang Andreas Weber A1 Matthias Eiber YR 2021 UL http://jnm.snmjournals.org/content/early/2021/03/12/jnumed.120.260091.abstract AB Purpose: Radiohybrid prostate-specific membrane antigen (rhPSMA) ligands are a new class of 18F-labeled PSMA-targeting agents. 18F-rhPSMA-7.3 is a lead compound which is currently under investigation in two multicenter phase III trials for PET-imaging. Here, we report the first retrospective data on its detection efficacy and potential impact on clinical management in a homogeneous cohort of patients with biochemical recurrence after radical prostatectomy, and prior to any salvage therapy. Methods: 242 patients (median [range] PSA, 0.60 [0.2–60.8] ng/mL) who underwent 18F-rhPSMA-7.3 PET/CT were retrospectively selected from the institutions' database. Images were re-read by an experienced nuclear medicine physician. Lesion detection rates were stratified by PSA. Further, potential management before and after PET was assessed by an interdisciplinary simulated tumor board and categorized (major vs. minor vs. no therapeutic change). The distribution of management change identified in each PSA subgroup was determined. Results: In total, 176/242 (72.7%) patients showed PSMA-ligand positive findings. 18F-rhPSMA-7.3 detection rates were 61.8% (63/102), 67.9% (38/56), 81.1% (30/37) and 95.7% (45/47) for PSA-levels of 0.2–<0.5 ng/mL, 0.5–<1 ng/mL, 1–<2 ng/mL and ≥2 ng/mL, respectively. 18F-rhPSMA-7.3 PET/CT revealed local recurrence, pelvic lymph node metastases, retroperitoneal lymph nodes metastases, supradiaphragmatic lymph nodes, bone metastases, and visceral metastases in 48.8% (n = 118), 28.9% (n = 70), 6.6% (n = 16), 1.2% (n = 3), 13.2% (n = 32) and 1.2% (n = 3) of patients, respectively. Notably, bone lesions were identified in 8.8% of patients (9/102) with PSA <0.5 ng/mL. Results from the interdisciplinary simulated tumor board indicated change of therapeutic management in 153/242 patients (63.2%) with 54/242 (22.3%) considered major and 99/242 (40.9%) minor, respectively. 18F-rhPSMA-7.3 PET/CT did not prompt any therapeutic changes in 64/242 patients (26.4%). Conclusion: 18F-rhPSMA-7.3 PET offers high detection efficacy in patients with biochemical recurrence after radical prostatectomy, and prior to potential salvage therapy, and results in a potential change in treatment plans in nearly 2/3 of patients. Keywords: Biochemical recurrence; hybrid imaging; positron emission tomography; prostate cancer; prostate‐specific membrane antigen.