Division of Nuclear Medicine, Diagnostic Department, Geneva University Hospital, Geneva, Switzerland;
Division of Radiology, Diagnostic Department, Geneva University Hospital, Geneva, Switzerland.
J Nucl Med. 2024 Sep 3;65(9):1376-1382. doi: 10.2967/jnumed.124.267899.
In up to two thirds of prostate-specific membrane antigen (PSMA) PET scans, unspecific bone uptake has been described. The aim of this study was to estimate the diagnostic accuracy of [Ga]Ga-PSMA-11 PET/CT for bone metastases and the occurrence of equivocal lesions. We analyzed retrospectively 118 patients who underwent a [Ga]Ga-PSMA-11 PET/CT for initial staging or recurrence evaluation. Lesions were interpreted according to the PSMA reporting and data system (PSMA-RADS) and the prostate cancer molecular imaging standardized evaluation (PROMISE) criteria. The SUV and the localization of each lesion were recorded. A combination of prior or follow-up examinations was used as a reference standard to categorize benign and malignant lesions. Correlation between the final diagnosis and imaging or clinicobiochemical parameters was tested. The diagnostic accuracy was calculated for different cutoffs of PSMA-RADS criteria, for PROMISE criteria, and the sequential combination of both. In total, 265 bone abnormalities were identified in 70 of 118 patients. Among these, 148 (55.8%) lesions in 50 (42.4%) patients were classified as PSMA-RADS-3B. There were no PSMA-RADS-3D lesions in our cohort. Equivocal lesions were more frequent on the ribs (30.6%) followed by the pelvis (26.5%), but in the ribs, such an uptake was malignant in 33.3% of cases versus 66.7% in the pelvis. A significant association was found between the final diagnosis and the SUV, prostate-specific antigen (PSA), PSA doubling time, International Society of Urological Pathology score, and the number of foci. The sensitivity and specificity were 100% and 63.6% for the PSMA-RADS-3B cutoff, respectively; 40.5% and 100% for the PSMA-RADS-4 cutoff, respectively; and 89.3% and 96.6% for both the PROMISE criteria and the sequential PSMA-RADS/PROMISE strategy, respectively. In the sequential method, the number of equivocal lesions was reduced from 147 to 2. We found that 53% of PSMA-RADS-3B lesions were malignant; 95.5% of lesions classified positive by the sequential method were true positives, whereas 32.6% were false negatives. [Ga]Ga-PSMA-11 PET/CT has high accuracy for the diagnosis of bone metastases. Equivocal lesions constitute nearly half of the lesions seen on PSMA PET. The sequential combination of PSMA-RADS and PROMISE criteria reduces the number of lesions classified as equivocal. PSMA-RADS-3B lesions which are positive according to the PROMISE criteria should be considered highly suggestive of malignancy.
在多达三分之二的前列腺特异性膜抗原 (PSMA) PET 扫描中，已经描述了非特异性骨摄取。本研究的目的是估计 [Ga]Ga-PSMA-11 PET/CT 对骨转移和可疑病变的诊断准确性。我们回顾性分析了 118 例接受 [Ga]Ga-PSMA-11 PET/CT 进行初始分期或复发评估的患者。病变根据 PSMA 报告和数据系统 (PSMA-RADS) 和前列腺癌分子成像标准化评估 (PROMISE) 标准进行解读。记录了每个病变的 SUV 和定位。将先前或后续检查的组合用作良性和恶性病变的参考标准进行分类。测试了最终诊断与影像学或临床生物化学参数之间的相关性。计算了不同 PSMA-RADS 标准、PROMISE 标准和两者连续组合的诊断准确性。总共在 70 名 118 名患者中发现了 265 个骨骼异常。其中，50 名患者 (42.4%) 的 148 个病变 (55.8%) 被归类为 PSMA-RADS-3B。我们的队列中没有 PSMA-RADS-3D 病变。在肋骨上更常见可疑病变 (30.6%)，其次是骨盆 (26.5%)，但在肋骨中，这种摄取在 33.3%的病例中是恶性的，而在骨盆中是 66.7%。最终诊断与 SUV、前列腺特异性抗原 (PSA)、PSA 倍增时间、国际泌尿病理学会评分和病灶数量之间存在显著相关性。PSMA-RADS-3B 截止值的灵敏度和特异性分别为 100%和 63.6%；PSMA-RADS-4 截止值分别为 40.5%和 100%；PROMISE 标准和连续 PSMA-RADS/PROMISE 策略的灵敏度和特异性分别为 89.3%和 96.6%。在连续方法中，可疑病变的数量从 147 个减少到 2 个。我们发现 53%的 PSMA-RADS-3B 病变是恶性的；通过连续方法分类为阳性的病变中，95.5%为真阳性，而 32.6%为假阴性。[Ga]Ga-PSMA-11 PET/CT 对骨转移的诊断具有很高的准确性。可疑病变构成 PSMA PET 上所见病变的近一半。PSMA-RADS 和 PROMISE 标准的连续组合减少了被归类为可疑的病变数量。根据 PROMISE 标准为阳性的 PSMA-RADS-3B 病变应被认为高度提示恶性。
