PDF(Pubmed)
Abstract：
BACKGROUND: In patients with increasing PSA and suspicion for prostate cancer, but previous negative biopsies, PET/MRI is used to test for tumours and target potential following biopsy. We aimed to determine different PSMA PET timing effects on signal kinetics and test its correlation with the patients\' PSA and Gleason scores (GS).
METHODS: A total of 100 patients were examined for 900 s using PET/MRI approximately 1-2 h p.i. depending on the tracer used (68Ga-PSMA-11, 18F-PSMA-1007 or 18F-rhPSMA7). The scans were reconstructed in static and dynamic mode (6 equal frames capturing \"late\" PSMA dynamics). TACs were computed for detected lesions as well as linear regression plots against time for static (SUV) and dynamic (SUV, SUL, and percent injected dose per gram) parameters. All computed trends were tested for correlation with PSA and GS.
RESULTS: Static and dynamic scans allowed unchanged lesion detection despite the difference in statistics. For all tracers, the lesions in the pelvic lymph nodes and bones had a mostly negative activity concentration trend (78% and 68%, resp.), while a mostly positive, stronger trend was found for the lesions in the prostate and prostatic fossa following RPE (84% and 83%, resp.). In case of 68Ga-PSMA-11, a strong negative (Rmin = - 0.62, Rmax = - 0.73) correlation was found between the dynamic parameters and the PSA. 18F-PSMA-1007 dynamic data showed no correlation with PSA, while for 18F-rhPSMA7 dynamic data, it was consistently low positive (Rmin = 0.29, Rmax = 0.33). All tracers showed only moderate correlation against GS (Rmin = 0.41, Rmax = 0.48). The static parameters showed weak correlation with PSA (Rmin = 0.24, Rmax = 0.36) and no correlation with GS.
CONCLUSIONS: \"Late\" dynamic PSMA data provided additional insight into the PSMA kinetics. While a stable moderate correlation was found between the PSMA kinetics in pelvic lesions and GS, a significantly variable correlation with the PSA values was shown depending on the radiotracer used, the highest being consistently for 68Ga-PSMA-11. We reason that with such late dynamics, the PSMA kinetics are relatively stable and imaging could even take place at earlier time points as is now in the clinical routine.
METHODS: A total of 100 patients were examined for 900 s using PET/MRI approximately 1-2 h p.i. depending on the tracer used (68Ga-PSMA-11, 18F-PSMA-1007 or 18F-rhPSMA7). The scans were reconstructed in static and dynamic mode (6 equal frames capturing \"late\" PSMA dynamics). TACs were computed for detected lesions as well as linear regression plots against time for static (SUV) and dynamic (SUV, SUL, and percent injected dose per gram) parameters. All computed trends were tested for correlation with PSA and GS.
RESULTS: Static and dynamic scans allowed unchanged lesion detection despite the difference in statistics. For all tracers, the lesions in the pelvic lymph nodes and bones had a mostly negative activity concentration trend (78% and 68%, resp.), while a mostly positive, stronger trend was found for the lesions in the prostate and prostatic fossa following RPE (84% and 83%, resp.). In case of 68Ga-PSMA-11, a strong negative (Rmin = - 0.62, Rmax = - 0.73) correlation was found between the dynamic parameters and the PSA. 18F-PSMA-1007 dynamic data showed no correlation with PSA, while for 18F-rhPSMA7 dynamic data, it was consistently low positive (Rmin = 0.29, Rmax = 0.33). All tracers showed only moderate correlation against GS (Rmin = 0.41, Rmax = 0.48). The static parameters showed weak correlation with PSA (Rmin = 0.24, Rmax = 0.36) and no correlation with GS.
CONCLUSIONS: \"Late\" dynamic PSMA data provided additional insight into the PSMA kinetics. While a stable moderate correlation was found between the PSMA kinetics in pelvic lesions and GS, a significantly variable correlation with the PSA values was shown depending on the radiotracer used, the highest being consistently for 68Ga-PSMA-11. We reason that with such late dynamics, the PSMA kinetics are relatively stable and imaging could even take place at earlier time points as is now in the clinical routine.
摘要：
背景：在PSA升高且怀疑前列腺癌的患者中，但之前的活检阴性,PET/MRI用于在活检后测试肿瘤和靶电位。我们旨在确定PSMAPET对信号动力学的不同时序影响，并检验其与患者PSA和Gleason评分（GS）的相关性。
方法：根据所使用的示踪剂（68Ga-PSMA-11，18F-PSMA-1007或18F-rhPSMA7），使用PET/MRI检查了100例患者900s。在静态和动态模式下重建扫描（6个相等的帧捕获“后期”PSMA动态）。计算检测到的病变的TAC，以及静态(SUV)和动态(SUV，SUL,和每克注射剂量百分比)参数。测试所有计算的趋势与PSA和GS的相关性。
结果：静态和动态扫描允许未改变的病变检测，尽管在统计学上存在差异。对于所有示踪剂，盆腔淋巴结和骨骼中的病变具有大多数负活性浓度趋势（78％和68％，resp.),虽然大部分是积极的，RPE后前列腺和前列腺窝病变的趋势更强(84%和83%，resp.).在68Ga-PSMA-11的情况下,在动态参数和PSA之间发现了强的负相关性(Rmin=-0.62,Rmax=-0.73)。18F-PSMA-1007动态数据显示与PSA无相关性，而对于18F-rhPSMA7动态数据，始终呈低阳性(Rmin=0.29,Rmax=0.33).所有示踪剂仅显示与GS的中等相关性（Rmin=0.41，Rmax=0.48）。静态参数与PSA呈弱相关性(Rmin=0.24,Rmax=0.36),与GS无相关性。
结论：“晚期”动态PSMA数据提供了对PSMA动力学的进一步了解。虽然骨盆病变的PSMA动力学与GS之间存在稳定的中等相关性，显示了与PSA值的显着可变相关性，这取决于所使用的放射性示踪剂，最高的是一致的68Ga-PSMA-11。我们的理由是，在如此晚的动态下，PSMA动力学相对稳定,甚至可以像现在的临床常规那样在较早的时间点进行成像.
方法：根据所使用的示踪剂（68Ga-PSMA-11，18F-PSMA-1007或18F-rhPSMA7），使用PET/MRI检查了100例患者900s。在静态和动态模式下重建扫描（6个相等的帧捕获“后期”PSMA动态）。计算检测到的病变的TAC，以及静态(SUV)和动态(SUV，SUL,和每克注射剂量百分比)参数。测试所有计算的趋势与PSA和GS的相关性。
结果：静态和动态扫描允许未改变的病变检测，尽管在统计学上存在差异。对于所有示踪剂，盆腔淋巴结和骨骼中的病变具有大多数负活性浓度趋势（78％和68％，resp.),虽然大部分是积极的，RPE后前列腺和前列腺窝病变的趋势更强(84%和83%，resp.).在68Ga-PSMA-11的情况下,在动态参数和PSA之间发现了强的负相关性(Rmin=-0.62,Rmax=-0.73)。18F-PSMA-1007动态数据显示与PSA无相关性，而对于18F-rhPSMA7动态数据，始终呈低阳性(Rmin=0.29,Rmax=0.33).所有示踪剂仅显示与GS的中等相关性（Rmin=0.41，Rmax=0.48）。静态参数与PSA呈弱相关性(Rmin=0.24,Rmax=0.36),与GS无相关性。
结论：“晚期”动态PSMA数据提供了对PSMA动力学的进一步了解。虽然骨盆病变的PSMA动力学与GS之间存在稳定的中等相关性，显示了与PSA值的显着可变相关性，这取决于所使用的放射性示踪剂，最高的是一致的68Ga-PSMA-11。我们的理由是，在如此晚的动态下，PSMA动力学相对稳定,甚至可以像现在的临床常规那样在较早的时间点进行成像.
