PET using radiolabeled prostate-specific membrane antigen (PSMA) is now being more widely adopted as a valuable tool to evaluate patients with prostate cancer (PC). Recently, 3 different criteria for interpretation of PSMA PET were published: the European Association of Nuclear Medicine (EANM) criteria, the Prostate Cancer Molecular Imaging Standardized Evaluation criteria, and the PSMA Reporting and Data System. We compared these 3 criteria in terms of interreader, intrareader, and intercriteria agreement. Methods: Data from 104 patients prospectively enrolled in research protocols at our institution were retrospectively reviewed. The cohort consisted of 2 groups: 47 patients (mean age, 64.2 y old) who underwent Glu-NH-CO-NH-Lys-(Ahx)-[⁶⁸Ga(HBED-CC)] (⁶⁸Ga-PSMA11) PET/MRI for initial staging of biopsy-proven intermediate- or high-risk PC, and 57 patients (mean age, 70.5 y old) who underwent ⁶⁸Ga-PSMA11 PET/CT because of biochemically recurrent PC. Three nuclear medicine physicians independently evaluated all ⁶⁸Ga-PSMA11 PET/MRI and PET/CT studies according to the 3 interpretation criteria. Two of them reevaluated all studies 6 mo later in the same manner and masked to the initial reading. The Gwet agreement coefficient was calculated to evaluate interreader, intrareader, and intercriteria agreement based on the following sites: local lesion (primary tumor or prostate bed after radical prostatectomy), lymph node metastases, and other metastases. Results: In the PET/MRI group, interreader, intrareader, and intercriteria agreement ranged from substantial to almost perfect for any site according to all 3 criteria. In the PET/CT group, interreader agreement ranged from substantial to almost perfect except for judgment of distant metastases based on the PSMA Reporting and Data System (Gwet agreement coefficient, 0.57; moderate agreement), in which the most frequent cause of disagreement was lung nodules. Intrareader agreement ranged from substantial to almost perfect for any site according to all 3 criteria. Intercriteria agreement for each site was also substantial to almost perfect. Conclusion: Although the 3 published criteria have good interreader and intrareader reproducibility in evaluating ⁶⁸Ga-PSMA11 PET, there are some factors causing interreader disagreement. Further work is needed to address this issue.

使用放射性标记的前列腺特异性膜抗原（PSMA）的PET现在正被更广泛地用作评估前列腺癌（PC）患者的有价值的工具。最近，发布了3种不同的PSMA PET解释标准：欧洲核医学协会（EANM）标准，前列腺癌分子成像标准化评估标准以及PSMA报告和数据系统。我们按照阅读者之间，阅读者内部和准则之间的协议比较了这三个标准。方法：回顾性研究了104名前瞻性纳入本研究方案的患者的数据。该队列包括2组：47例患者（平均年龄64.2岁），他们接受了Glu-NH-CO-NH-Lys-（Ahx）-[ ⁶⁸ Ga（HBED-CC）]（⁶⁸Ga / PSMA11）PET / MRI，用于活检证实的中危或高危PC的初始分期，有57例患者（平均年龄70.5岁）由于生化复发性PC而接受了⁶⁸ Ga-PSMA11 PET / CT。三名核医学医师根据3个解释标准对^68项Ga-PSMA11 PET / MRI和PET / CT研究进行了独立评估。他们中的两个人在6个月后以相同的方式重新评估了所有研究，并掩盖了最初的阅读结果。计算Gwet一致性系数，以根据以下位点评估阅读器，阅读器内部和标准间的一致性：局部病变（根治性前列腺切除术后的原发肿瘤或前列腺床），淋巴结转移和其他转移。结果：在PET / MRI组中，根据所有这三个标准，对于任何站点，阅读器间，阅读器内和标准间的一致性从实质到几乎完美不等。在PET / CT组中，阅读者之间的一致性从实质到几乎完美，除了根据PSMA报告和数据系统判断远处转移（Gwet一致性系数，0.57；中度一致性），其中分歧的最常见原因是肺结节。根据所有3个标准，对于任何站点，阅读器内协议的范围从实质性到几乎完美。每个站点的标准间协议也很重要，几乎是完美的。结论：尽管3项发表的标准在评估^68方面具有良好的阅读者间和阅读者内重复性Ga-PSMA11 PET，有一些因素会引起读者之间的分歧。需要进一步的工作来解决这个问题。