背景静脉注射前列腺特异性膜抗原（PSMA）靶向放射配体治疗可提高患有转移性去势抵抗性前列腺癌的男性的生存率。然而，选择性前列腺动脉给药对原发性肿瘤摄取的影响尚不清楚。目的 使用动态 PET/CT 比较未经治疗的高危前列腺癌个体静脉注射和选择性前列腺动脉输注期间前列腺肿瘤体积 (VOIs) 中镓 68 (68Ga)-PSMA-11 的摄取情况。材料和方法 在这项在学术医疗中心进行的前瞻性个体比较研究中，2022 年 1 月至 2023 年 2 月期间，招募了 5 名年龄分别为 58、61、64、66 和 68 岁且患有初治前列腺癌的男性，并接受了两次动态 68Ga 治疗。 -PSMA-11 PET/CT 检查间隔 1 周。在第一次检查期间，放射性示踪剂通过静脉注射。在第二次给药期间，放射性示踪剂通过血管造影放置的微导管输送到右或左前列腺动脉。主要结果是前列腺肿瘤 VOI 的最大标准化摄取值 (SUVmax)。次要结果包括前列腺肿瘤 VOI 的平均 SUV (SUVmean) 和 SUVmean 曲线下面积 (AUC)。使用纵向混合效应模型来比较动态 SUVmax 和 SUVmean 时间活动曲线 (TAC)，并对其余数据使用配对 t 检验。结果 肿瘤 VOI 内的平均 SUVmax 对于静脉会话为 14（范围，3-43），对于动脉会话为 938（范围，460-1436）（P = .008）。总体而言，动脉会话期间 VOI 内的 SUV 平均值更大 (P < .001)，在峰值摄取和最终时间点分别高出 46 倍和 19 倍。动脉 TAC 的平均 AUC 高于静脉 TAC，分别为 14600 SUV × min（范围，8353-20025 SUV × min）和 240 SUV × min（范围，69-622 SUV × min）（P = .002） 。结论 选择性前列腺动脉输注比静脉输注产生更大的 68Ga-PSMA-11 肿瘤 SUV。在高危前列腺癌中，有必要进一步研究局部区域、动脉内递送 PSMA 靶向治疗诊断剂。 ClinicalTrials.gov 标识符：NCT04976257 © RSNA，2024 本文提供补充材料。另请参阅本期 Civelek 的社论。

Background Intravenous prostate-specific membrane antigen (PSMA)-targeted radioligand therapy improves survival in men with metastatic castration-resistant prostate cancer. Yet, the impact of selective prostatic arterial administration on primary tumor uptake is unclear. Purpose To compare gallium 68 (68Ga)-PSMA-11 uptake using dynamic PET/CT in prostatic tumoral volumes of interest (VOIs) during intravenous and selective prostatic arterial infusions for individuals with untreated, high-risk prostate cancer. Materials and Methods In this prospective, intraindividual comparative study conducted at an academic medical center, five men aged 58, 61, 64, 66, and 68 years with treatment-naive prostate cancer were enrolled between January 2022 and February 2023 and underwent two dynamic 68Ga-PSMA-11 PET/CT examinations 1 week apart. During the first examination, the radiotracer was administered intravenously. During the second administration, the radiotracer was delivered into either the right or left prostatic artery through an angiographically placed microcatheter. The primary outcome was maximum standardized uptake value (SUVmax) in prostatic tumoral VOIs. The secondary outcomes included mean SUV (SUVmean) in prostatic tumoral VOIs and area under the SUVmean curves (AUC). Longitudinal mixed-effects models were used to compare dynamic SUVmax and SUVmean time-activity curves (TACs), and paired t tests were used for the remaining data. Results The mean SUVmax within tumoral VOIs was 14 (range, 3-43) for venous sessions and 938 (range, 460-1436) for arterial sessions (P = .008). The SUVmean within VOIs was greater during arterial sessions (P < .001) overall and 46-fold and 19-fold greater at peak uptake and final time points, respectively. The mean AUC was greater on arterial TACs than on venous TACs at 14600 SUV × min (range, 8353-20025 SUV × min) and 240 SUV × min (range, 69-622 SUV × min), respectively (P = .002). Conclusion Selective prostatic arterial infusion resulted in greater 68Ga-PSMA-11 tumoral SUV than intravenous infusion. Further study of local-regional, intra-arterial delivery of a PSMA-targeted theranostic agent is warranted in high-risk prostate cancer. ClinicalTrials.gov identifier: NCT04976257 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Civelek in this issue.