Eiber Matthias, Maurer Tobias, Souvatzoglou Michael, Beer Ambros J, Ruffani Alexander, Haller Bernhard, Graner Frank-Philipp, Kübler Hubert, Haberkorn Uwe, Eisenhut Michael, Wester Hans-Jürgen, Gschwend Jürgen E, Schwaiger Markus
Department of Nuclear Medicine, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany Department of Radiology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany
Department of Urology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
J Nucl Med. 2015 May;56(5):668-74. doi: 10.2967/jnumed.115.154153. Epub 2015 Mar 19.
The expression of prostate-specific membrane antigen (PSMA) is increased in prostate cancer. Recently, (68)Ga-PSMA (Glu-NH-CO-NH-Lys-(Ahx)-[(68)Ga(HBED-CC)]) was developed as a PSMA ligand. The aim of this study was to investigate the detection rate of (68)Ga-PSMA PET/CT in patients with biochemical recurrence after radical prostatectomy.
Two hundred forty-eight of 393 patients were evaluable for a retrospective analysis. Median prostate-specific antigen (PSA) level was 1.99 ng/mL (range, 0.2-59.4 ng/mL). All patients underwent contrast-enhanced PET/CT after injection of 155 ± 27 MBq of (68)Ga-PSMA ligand. The detection rates were correlated with PSA level and PSA kinetics. The influence of antihormonal treatment, primary Gleason score, and contribution of PET and morphologic imaging to the final diagnosis were assessed.
Two hundred twenty-two (89.5%) patients showed pathologic findings in (68)Ga-PSMA ligand PET/CT. The detection rates were 96.8%, 93.0%, 72.7%, and 57.9% for PSA levels of ≥2, 1 to <2, 0.5 to <1, and 0.2 to <0.5 ng/mL, respectively. Whereas detection rates increased with a higher PSA velocity (81.8%, 82.4%, 92.1%, and 100% in <1, 1 to <2, 2 to <5, and ≥5 ng/mL/y, respectively), no significant association could be found for PSA doubling time (82.7%, 96.2%, and 90.7% in >6, 4-6, and <4 mo, respectively). (68)Ga-PSMA ligand PET (as compared with CT) exclusively provided pathologic findings in 81 (32.7%) patients. In 61 (24.6%) patients, it exclusively identified additional involved regions. In higher Gleason score (≤7 vs. ≥8), detection efficacy was significantly increased (P = 0.0190). No significant difference in detection efficacy was present regarding antiandrogen therapy (P = 0.0783).
Hybrid (68)Ga-PSMA ligand PET/CT shows substantially higher detection rates than reported for other imaging modalities. Most importantly, it reveals a high number of positive findings in the clinically important range of low PSA values (<0.5 ng/mL), which in many cases can substantially influence the further clinical management.
前列腺特异性膜抗原（PSMA）在前列腺癌中表达增加。最近，（68）Ga-PSMA（Glu-NH-CO-NH-Lys-(Ahx)-[(68)Ga(HBED-CC)]）被开发为一种PSMA配体。本研究的目的是调查（68）Ga-PSMA PET/CT在根治性前列腺切除术后生化复发患者中的检出率。
393例患者中的248例可进行回顾性分析。前列腺特异性抗原（PSA）中位数水平为1.99 ng/mL（范围为0.2 - 59.4 ng/mL）。所有患者在注射155±27 MBq的（68）Ga-PSMA配体后接受对比增强PET/CT检查。将检出率与PSA水平和PSA动力学相关联。评估抗激素治疗、原发性Gleason评分以及PET和形态学成像对最终诊断的贡献。
222例（89.5%）患者在（68）Ga-PSMA配体PET/CT中显示出病理结果。PSA水平≥2、1至<2、0.5至<1和0.2至<0.5 ng/mL时的检出率分别为96.8%、93.0%、72.7%和57.9%。虽然检出率随PSA速度升高而增加（PSA速度<1、1至<2、2至<5和≥5 ng/mL/年时分别为81.8%、82.4%、92.1%和100%），但PSA倍增时间与检出率无显著相关性（PSA倍增时间>6、4 - 6和<4个月时分别为82.7%、96.2%和90.7%）。（68）Ga-PSMA配体PET（与CT相比）仅在81例（32.7%）患者中提供了病理结果。在61例（24.6%）患者中，它仅识别出额外的受累区域。在较高的Gleason评分（≤7与≥8）中，检测效能显著增加（P = 0.0190）。抗雄激素治疗对检测效能无显著差异（P = 0.0783）。
（68）Ga-PSMA配体PET/CT融合显像显示出比其他成像方式更高的检出率。最重要的是，它在低PSA值（<0.5 ng/mL）这一临床重要范围内发现了大量阳性结果，在许多情况下可显著影响进一步的临床管理。
