Nuclear Medicine Department, Humanitas Clinical and Research Hospital, Milan, Italy.
Urology Department, Humanitas Clinical and Research Hospital, Milan, Italy.
J Urol. 2018 Jul;200(1):95-103. doi: 10.1016/j.juro.2018.01.079. Epub 2018 Feb 1.
Ga labeled prostate specific membrane antigen positron emission tomography/computerized tomography may represent the most promising imaging modality to identify and risk stratify prostate cancer in patients with contraindications to or negative multiparametric magnetic resonance imaging.
In this prospective observational study we analyzed Ga labeled prostate specific membrane antigen positron emission tomography/computerized tomography in a select group of patients with persistently elevated prostate specific antigen and/or Prostate Health Index suspicious for prostate cancer, negative digital rectal examination and at least 1 negative biopsy. The cohort comprised men with equivocal multiparametric magnetic resonance imaging (Prostate Imaging-Reporting and Data System, version 2 score of 2 or less), or an absolute or relative contraindication to multiparametric magnetic resonance imaging. Sensitivity, specificity and CIs were calculated compared to histopathology findings. ROC analysis was applied to determine the optimal cutoff values of Ga labeled prostate specific membrane antigen uptake to identify clinically significant prostate cancer (Gleason score 7 or greater).
A total of 45 patients with a median age of 64 years were referred for Ga labeled prostate specific membrane antigen positron emission tomography/computerized tomography between January and August 2017. The 25 patients (55.5%) considered to have positive positron emission tomography results underwent software assisted fusion biopsy. We determined the uptake values of regions of interest, including a median maximum standardized uptake value of 5.34 (range 2.25 to 30.41) and a maximum-to-background standardized uptake value ratio of 1.99 (range 1.06 to 14.42). Mean and median uptake values on Ga labeled prostate specific membrane antigen positron emission tomography/computerized tomography (ie the maximum standardized uptake value or the maximum-to-background standardized uptake value ratio) were significantly higher for Gleason score 7 lesions than for Gleason score 6 or benign lesions (p <0.001). On ROC analysis a maximum standardized uptake value of 5.4 and a maximum-to-background standardized uptake value ratio of 2 discriminated clinically relevant prostate cancer with 100% overall sensitivity in each case, and 76% and 88% specificity, respectively.
Our findings support the use of Ga labeled prostate specific membrane antigen positron emission tomography/computerized tomography for primary detection of prostate cancer in a specific subset of men.
Ga 标记的前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描可能代表最有前途的成像方式，可用于识别和风险分层有禁忌或多参数磁共振成像呈阴性的前列腺癌患者的前列腺癌。
在这项前瞻性观察研究中，我们分析了一组选择的患者的 Ga 标记的前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描，这些患者的前列腺特异性抗原持续升高和/或前列腺健康指数可疑前列腺癌，数字直肠检查阴性，且至少有 1 次阴性活检。该队列包括多参数磁共振成像结果不确定的男性（前列腺成像报告和数据系统，版本 2 评分 2 或更低），或多参数磁共振成像有绝对或相对禁忌证的男性。与组织病理学结果相比，计算了敏感性、特异性和置信区间。应用 ROC 分析确定 Ga 标记的前列腺特异性膜抗原摄取的最佳截断值以识别临床显著的前列腺癌（Gleason 评分 7 或更高）。
2017 年 1 月至 8 月期间，共有 45 名中位年龄为 64 岁的患者因 Ga 标记的前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描而转诊。25 名（55.5%）被认为正电子发射断层扫描结果阳性的患者接受了软件辅助融合活检。我们确定了感兴趣区域的摄取值，包括中位最大标准化摄取值 5.34（范围 2.25 至 30.41）和最大至背景标准化摄取值比 1.99（范围 1.06 至 14.42）。Ga 标记的前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描上的平均和中位数摄取值（即最大标准化摄取值或最大至背景标准化摄取值比）在 Gleason 评分 7 病变中明显高于 Gleason 评分 6 或良性病变（p<0.001）。在 ROC 分析中，最大标准化摄取值为 5.4，最大至背景标准化摄取值比为 2，以 100%的总敏感性分别区分有临床意义的前列腺癌，特异性分别为 76%和 88%。
我们的研究结果支持 Ga 标记的前列腺特异性膜抗原正电子发射断层扫描/计算机断层扫描在特定亚组男性中用于前列腺癌的初次检测。
