METHODS: Newly diagnosed or recurrent prostate cancer patients enrolled in LIGHTHOUSE (NCT04186819) or SPOTLIGHT (NCT04186845), respectively, underwent PET/CT 50-70 min after intravenous administration of 296 MBq 18F-flotufolastat. For the present analysis, 718 18F-flotufolastat scans (352 from LIGHTHOUSE and 366 from SPOTLIGHT) were re-evaluated by three board-certified nuclear medicine physicians. Reader 1 performed a quantitative assessment (SUVmax and SUVmean) of bladder activity in a circular region-of-interest over the maximum diameter of bladder activity in the transverse plane. All three readers qualitatively assessed the impact of any urinary activity in the bladder on image interpretation using a three-point scale (0 = no/minimal visible urinary activity, 1 = urinary activity visible but distinction between urine and disease possible and 2 = assessment inhibited by urinary activity) and the presence/absence of ureteric activity and halo artifacts.
RESULTS: In total, 712/718 scans were evaluable. Reasons for exclusion were cystectomy, renal failure, or urinary catheter in situ (n = 2 each). The median bladder SUVmax and SUVmean were 17.1 and 12.5, respectively. By majority read, 682/712 (96%) patients had either no urinary activity (score = 0) or visible activity that could be distinguished from disease uptake (score = 1). In the minority of patients (24, 3.4%) where urinary activity did impact assessment (score = 2), the median bladder SUVmean was higher (20.5) than those scored 0 (3.8) or 1 (14.0). Ureteric activity was absent in 401 (56%) patients. Halo artifacts were observed in only two (0.3%) patients (majority read).
CONCLUSIONS: 18F-Flotufolastat urinary activity did not influence disease assessment for the majority of patients. While this study was not designed as a head-to-head comparison, the median bladder SUVs are lower than previously reported values for other renally cleared PSMA-PET radiopharmaceuticals.
方法:新诊断或复发性前列腺癌患者纳入LIGHTHOUSE(NCT04186819)或SPOTLIGHT(NCT04186845),分别,静脉注射296MBq18F-flofufolastat后50-70分钟接受PET/CT检查。对于目前的分析,718次18F-flotufolastat扫描(352次来自LIGHTHOUSE和366次来自SPOTLIGHT)由三名委员会认证的核医学医师重新评估。读者1对在横向平面中膀胱活动的最大直径上的圆形感兴趣区域中的膀胱活动进行了定量评估(SUVmax和SUVmean)。所有三位读者都使用三点量表(0=无/最小可见尿液活动,1=可见的尿液活动,但尿液与可能的疾病之间存在区别,2=被尿液活动抑制的评估)以及输尿管活动和光环伪影的存在/不存在。
结果:总计,712/718扫描是可评估的。排除的原因是膀胱切除术,肾功能衰竭,或原位导尿管(每个n=2)。中位膀胱SUVmax和SUVmean分别为17.1和12.5。大多数人阅读,682/712(96%)患者没有泌尿活动(评分=0)或可见活动,可以与疾病摄取区分开(评分=1)。在少数患者(24,3.4%),其中尿路活动确实影响评估(得分=2),中位膀胱SUV均值(20.5)高于0分(3.8)或1分(14.0).401例(56%)患者没有输尿管活动。仅在两名(0.3%)患者中观察到光环伪影(大多数读数)。
结论:对于大多数患者,18F-Flotufolastat的排尿活动不影响疾病评估。虽然这项研究不是作为头对头比较设计的,膀胱SUV的中位数低于先前报告的其他肾清除PSMA-PET放射性药物的值.