Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, California
Department of Nuclear Medicine, Ludwig-Maximilians-University Munich, Munich, Germany.
J Nucl Med. 2017 Oct;58(10):1617-1623. doi: 10.2967/jnumed.117.190827. Epub 2017 Apr 13.
The interobserver agreement for Ga-PSMA-11 PET/CT study interpretations in patients with prostate cancer is unknown. Ga-PSMA-11 PET/CT was performed in 50 patients with prostate cancer for biochemical recurrence ( = 25), primary diagnosis ( = 10), biochemical persistence after primary therapy ( = 5), or staging of known metastatic disease ( = 10). Images were reviewed by 16 observers who used a standardized approach for interpretation of local (T), nodal (N), bone (Mb), or visceral (Mc) involvement. Observers were classified as having a low (<30 prior Ga-PSMA-11 PET/CT studies; = 5), intermediate (30-300 studies; = 5), or high level of experience (>300 studies; = 6). Histopathology ( = 25, 50%), post-external-beam radiation therapy prostate-specific antigen response ( = 15, 30%), or follow-up PET/CT ( = 10, 20%) served as a standard of reference. Observer groups were compared by overall agreement (% patients matching the standard of reference) and Fleiss' κ with mean and corresponding 95% confidence interval (CI). Agreement among all observers was substantial for T (κ = 0.62; 95% CI, 0.59-0.64) and N (κ = 0.74; 95% CI, 0.71-0.76) staging and almost perfect for Mb (κ = 0.88; 95% CI, 0.86-0.91) staging. Level of experience positively correlated with agreement for T (κ = 0.73/0.66/0.50 for high/intermediate/low experience, respectively), N (κ = 0.80/0.76/0.64, respectively), and Mc staging (κ = 0.61/0.46/0.36, respectively). Interobserver agreement for Mb was almost perfect irrespective of prior experience (κ = 0.87/0.91/0.88, respectively). Observers with low experience, when compared with intermediate and high experience, demonstrated significantly lower median overall agreement (54% vs. 66% and 76%, = 0.041) and specificity for T staging (73% vs. 88% and 93%, = 0.032). The interpretation of Ga-PSMA-11 PET/CT for prostate cancer staging is highly consistent among observers with high levels of experience, especially for nodal and bone assessments. Initial training on at least 30 patient cases is recommended to ensure acceptable performance.
在前列腺癌患者中，Ga-PSMA-11 PET/CT 研究解读的观察者间一致性尚不清楚。50 例前列腺癌患者进行了 Ga-PSMA-11 PET/CT 检查，用于生化复发（=25）、原发性诊断（=10）、原发性治疗后生化持续存在（=5）或已知转移性疾病的分期（=10）。图像由 16 名观察者进行评估，他们使用标准化方法来评估局部（T）、淋巴结（N）、骨骼（Mb）或内脏（Mc）受累情况。观察者分为低经验组（<30 次 Ga-PSMA-11 PET/CT 检查；=5）、中经验组（30-300 次检查；=5）和高经验组（>300 次检查；=6）。组织病理学（=25，50%）、外照射后前列腺特异性抗原反应（=15，30%）或随访 PET/CT（=10，20%）作为参考标准。通过总体一致性（%与参考标准匹配的患者）和 Fleiss'κ（平均值及其相应的 95%置信区间[CI]）比较观察者组。所有观察者在 T（κ=0.62；95%CI，0.59-0.64）和 N（κ=0.74；95%CI，0.71-0.76）分期方面的一致性较高，在 Mb（κ=0.88；95%CI，0.86-0.91）分期方面的一致性几乎为完美。经验水平与 T（κ=0.73/0.66/0.50 分别为高/中/低经验）、N（κ=0.80/0.76/0.64，分别）和 Mc 分期（κ=0.61/0.46/0.36，分别）的一致性呈正相关。无论先前的经验如何，观察者对 Mb 的一致性几乎都是完美的（κ=0.87/0.91/0.88，分别）。与中、高经验相比，低经验观察者的总体一致性（54%比 66%和 76%，=0.041）和 T 分期的特异性（73%比 88%和 93%，=0.032）显著降低。在具有高水平经验的观察者中，Ga-PSMA-11 PET/CT 对前列腺癌分期的解读具有高度一致性，尤其是在评估淋巴结和骨骼方面。建议至少进行 30 例患者病例的初始培训，以确保可接受的性能。
