Recently, ⁶⁸Ga-labeled prostate-specific membrane antigen (PSMA)–ligand positron-emission tomography (PET) imaging has been shown to improve detection rates in recurrent prostate cancer (PC). However, published studies include only small patient numbers at low prostate-specific antigen (PSA) values. For this study, 272 consecutive patients with biochemical recurrence after radical prostatectomy and PSA value between 0.2 and 1 ng/ml were included. The ⁶⁸Ga-PSMA-ligand PET/computed tomography (CT) was evaluated, and detection rates were determined and correlated to various clinical variables using univariate and multivariable analyses. Subgroups of patients with very low (0.2–0.5 ng/ml) and low (>0.5–1.0 ng/ml) PSA values were analyzed. In total, lesions indicative of PC recurrence were detected in 55% (74/134) and 74% (102/138) with very low and low PSA values, respectively. Main sites of recurrence were pelvic or retroperitoneal lymph nodes metastases, followed by local recurrence and bone metastases with higher probability in the low versus very low PSA subgroup. Detection rates significantly increased with higher PSA values, primary pT ≥ 3a, primary pN+ disease, grade group ≥4, previous radiation therapy, and concurrent androgen deprivation therapy (ADT) in univariate analysis. In a multivariable logistic regression model, concurrent ADT and PSA values were identified as most relevant predictors of positive ⁶⁸Ga-PSMA-ligand PET/CT. Further, prediction nomograms were established, which may help in estimating pretest PSMA-ligand PET positivity in clinical practice.

Patient summary

In our study, ⁶⁸Ga-labeled prostate-specific membrane antigen (PSMA)–ligand positron-emission tomography (PET)/computed tomography (CT) detected recurrent disease after radical prostatectomy in 55% (74/134) and 74% (102/138) of patients with very low (0.2–0.5 ng/ml) and low (>0.5–1.0 ng/ml) prostate-specific antigen values, respectively. On the basis of these data, it seems reasonable to perform ⁶⁸Ga-PSMA-ligand PET/CT also in patients with early biochemical recurrence, as it can tailor further therapy decisions (eg, local vs systemic treatment). The established prediction nomograms can further assist urologists in discussions on the use of ⁶⁸Ga-PSMA-ligand PET/CT with their patients in specific clinical settings.

中文翻译：

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前列腺癌根治术后早期生化复发性前列腺癌中⁶⁸ Ga标记的前列腺特异性膜抗原－配体正电子发射断层显像/计算机断层显像的功效，预测因素和预测诺模图

最近，已显示⁶⁸ Ga标记的前列腺特异性膜抗原（PSMA）-配体正电子发射断层扫描（PET）成像可提高复发性前列腺癌（PC）的检出率。但是，已发表的研究仅包括低前列腺特异性抗原（PSA）值的少量患者。对于本研究，包括272例连续前列腺癌根治术后生化复发且PSA值在0.2和1 ng / ml之间的患者。在⁶⁸评估了Ga-PSMA配体PET /计算机断层扫描（CT），并使用单变量和多变量分析确定了检出率并将其与各种临床变量相关联。分析了PSA值极低（0.2-0.5 ng / ml）和极低（> 0.5-1.0 ng / ml）的患者亚组。总体而言，在55％（74/134）和74％（102/138）的PSA值非常低和很低的情况下，检测到PC复发的病变。复发的主要部位是骨盆或腹膜后淋巴结转移，其次是局部复发和骨转移，在低PSA组和极低PSA组中发生的可能性更高。在单变量分析中，较高的PSA值，原发性pT≥3a，原发性pN +疾病，≥4级组，既往放疗和同时进行雄激素剥夺治疗（ADT）时，检出率显着提高。⁶⁸ Ga-PSMA-配体PET / CT。此外，建立了预测列线图，这可能有助于估计临床实践中的预测试PSMA-配体PET阳性。

病人总结

在我们的研究中，有^68位Ga标记的前列腺特异性膜抗原（PSMA）-配体正电子发射断层扫描（PET）/计算机断层扫描（CT）在前列腺癌根治术后发现复发性疾病的比例分别为55％（74/134）和74％（102） / 138）分别具有非常低的前列腺特异性抗原值（0.2-0.5 ng / ml）和低（> 0.5-1.0 ng / ml）的患者。根据这些数据，在早期生化复发的患者中也进行⁶⁸ Ga-PSMA-配体PET / CT似乎是合理的，因为它可以调整进一步的治疗决策（例如，局部治疗与全身治疗）。建立的预测列线图可以进一步帮助泌尿科医师讨论在特定临床环境中与患者一起使用⁶⁸ Ga-PSMA-配体PET / CT的情况。