前列腺特异性膜抗原（PSMA）PET在分期前列腺癌患者中的准确性高于CT和骨扫描。我们不了解如何将基于传统成像的临床试验数据应用于使用PSMA PET进行分级的患者。因此，我们旨在评估骨扫描检测骨转移的能力，以PSMA PET作为参考标准。方法：在这项多中心回顾性诊断研究中，纳入了167例前列腺癌患者，他们在100天内接受了骨扫描和PSMA PET检查。每项研究由3名蒙面读者进行解读，并以PSMA PET的结果作为参考标准。终点是骨扫描的阳性预测值（PPV）、阴性预测值（NPV）和特异性。此外，还评估了读者间的一致性、阳性率、PSMA PET的摄取情况以及骨病损的数量。结果：共纳入了167例患者，其中77例进行了初始分期，60例处于生化复发和去势敏感前列腺癌设置，30例处于去势抵抗性前列腺癌设置。在所有患者中，骨扫描的PPV、NPV和特异性分别为0.73（95% CI，0.61-0.82）、0.82（95% CI，0.74-0.88）和0.82（95% CI，0.74-0.88）。在初始分期的患者中，骨扫描的PPV、NPV和特异性分别为0.43（95% CI，0.26-0.63）、0.94（95% CI，0.85-0.98）和0.80（95% CI，0.68-0.88）。骨扫描的骨病损的读者间一致性中等（Fleiss κ，0.51），而PSMA PET参考标准的一致性较高（Fleiss κ，0.80）。结论：在这项多中心回顾性研究中，初始分期患者骨扫描的PPV较低，57%的阳性骨扫描结果是假阳性。这表明，骨扫描将低体积转移病灶的患者误诊为局部病变的比例较大。这一点在将STAMPEDE M1放射治疗试验等临床数据应用于使用PSMA PET进行分级的患者时至关重要。© 2023年核医学与分子成像学会

Prostate-specific membrane antigen (PSMA) PET has a higher accuracy than CT and bone scans to stage patients with prostate cancer. We do not understand how to apply clinical trial data based on conventional imaging to patients staged using PSMA PET. Therefore, we aimed to evaluate the ability of bone scans to detect osseous metastases using PSMA PET as a reference standard. Methods: In this multicenter retrospective diagnostic study, 167 patients with prostate cancer, who were imaged with bone scans and PSMA PET performed within 100 d, were included for analysis. Each study was interpreted by 3 masked readers, and the results of the PSMA PET were used as the reference standard. Endpoints were positive predictive value (PPV), negative predictive value (NPV), and specificity for bone scans. Additionally, interreader reproducibility, positivity rate, uptake on PSMA PET, and the number of lesions were evaluated. Results: In total, 167 patients were included, with 77 at initial staging, 60 in the biochemical recurrence and castration-sensitive prostate cancer setting, and 30 in the castration-resistant prostate cancer setting. In all patients, the PPV, NPV, and specificity for bone scans were 0.73 (95% CI, 0.61-0.82), 0.82 (95% CI, 0.74-0.88), and 0.82 (95% CI, 0.74-0.88), respectively. In patients at initial staging, the PPV, NPV, and specificity for bone scans were 0.43 (95% CI, 0.26-0.63), 0.94 (95% CI, 0.85-0.98), and 0.80 (95% CI, 0.68-0.88), respectively. Interreader agreement for bone disease was moderate for bone scans (Fleiss κ, 0.51) and substantial for the PSMA PET reference standard (Fleiss κ, 0.80). Conclusion: In this multicenter retrospective study, the PPV of bone scans was low in patients at initial staging, with 57% of positive bone scans being false positives. This suggests that a large proportion of patients considered low-volume metastatic by the bone scan actually had localized disease, which is critical when applying clinical data from trials such as the STAMPEDE M1 radiation therapy trial to patients being staged with PSMA PET.© 2023 by the Society of Nuclear Medicine and Molecular Imaging.