Our aim was to evaluate the interobserver agreement in ¹⁸F-sodium fluoride (NaF) PET/CT for the detection of bone metastases in patients with prostate cancer (PCa). Methods: ¹⁸F-NaF PET/CT scans were retrieved from all patients who participated in 4 recent prospective trials. Two experienced observers independently evaluated the ¹⁸F-NaF PET/CT scans on a patient level using a 3-category scale (no bone metastases [M0], equivocal for bone metastases, and bone metastases present [M1]) and on a dichotomous scale (M0/M1). In patients with no more than 10 lesions, the location and number of lesions were recorded. On a patient level, the diagnostic performance was calculated using a sensitivity analysis, in which equivocal lesions were handled as M0 as well as M1. Results: ¹⁸F-NaF PET/CT scans from 219 patients with PCa were included, of whom 129 patients were scanned for primary staging, 67 for biochemical recurrence, and 23 for metastatic castration-resistant PCa. Agreement between the observers was almost perfect on a patient level (3-category unweighted κ = 0.83 ± 0.05, linear weighted κ = 0.90 ± 0.06, and dichotomous κ = 0.91 ± 0.07). On a lesion level (dichotomous scale), the observers agreed on the number and location of bone metastases in 205 (93.6%) patients. In the remaining 14 patients, the readers disagreed on the number of lesions in 13 patients and the location of bone metastases in 1 patient. A final diagnosis of bone metastases was made for 211 of 219 patients. The sensitivity ranged from 0.86 to 0.92, specificity from 0.83 to 0.97, positive predictive value from 0.70 to 0.93, and negative predictive value from 0.94 to 0.96. Conclusion: The interobserver agreement on ¹⁸F-NaF PET/CT for the detection of bone metastases in patients with PCa was very high among trained observers, both on a patient level and on a lesion level. Moreover, the diagnostic performance of ¹⁸F-NaF PET/CT was satisfactory, rendering ¹⁸F-NaF PET/CT a robust tool in the diagnostic armamentarium.

我们的目的是评估¹⁸ F-氟化钠（NaF）PET / CT中观察者之间的协议，以检测前列腺癌（PCa）患者的骨转移。方法： 从所有参加了4个近期前瞻性试验的患者中检索出^18个F-NaF PET / CT扫描。两名经验丰富的观察员独立评估了¹⁸F-NaF PET / CT使用三分类量表（无骨转移[M0]，模棱两可，并且存在骨转移[M1]）和二分法（M0 / M1）在患者水平进行扫描。在病变不超过10个的患者中，记录病变的位置和数量。在患者水平上，使用敏感性分析计算诊断性能，其中模棱两可的病变被处理为M0和M1。结果： ¹⁸包括219例PCa患者的F-NaF PET / CT扫描，其中扫描129例患者的主要分期，67例生化复发和23例转移性去势抵抗性PCa。观察者之间的协议在患者水平上几乎是完美的（3类未加权κ= 0.83±0.05，线性加权κ= 0.90±0.06和二分κ= 0.91±0.07）。在病变水平（二分法）上，观察者同意了205名（93.6％）患者的骨转移的数量和位置。在其余14例患者中，读者不同意13例患者的病变数目和1例患者的骨转移位置。对219位患者中的211位进行了骨转移的最终诊断。敏感性范围为0.86至0.92，特异性范围为0.83至0.97，阳性预测值为0.70至0.93，结论：在受过培训的观察者中，无论是在患者水平还是在病灶水平上，观察者之间就¹⁸ F-NaF PET / CT在PCa患者中检测骨转移的共识非常高。此外，¹⁸ F-NaF PET / CT的诊断性能令人满意，使¹⁸ F-NaF PET / CT成为诊断武器库中的强大工具。