Division of Urology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy; Università degli studi di Bologna, Bologna, Italy.
Division of Nuclear Medicine, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.
Eur Urol Oncol. 2023 Feb;6(1):41-48. doi: 10.1016/j.euo.2021.12.002. Epub 2021 Dec 20.
A nomogram has recently been developed to predict Ga-labeled prostate-specific membrane antigen (PSMA)-11 positron emission tomography (PET)/computed tomography (PSMA-PET) results in recurrent prostate cancer (PCa) patients.
To perform external validation of the original nomogram in a multicentric setting.
DESIGN, SETTING, AND PARTICIPANTS: A total of 1639 patients who underwent PSMA-PET for prostate-specific antigen (PSA) relapse after radical therapy were retrospectively included from six high-volume PET centers. The external cohort was stratified according to clinical setting categories: group 1: first-time biochemical recurrence (n = 774); group 2: PSA relapse after salvage therapy (n = 499); group-3: biochemical persistence after radical prostatectomy (n = 210); and group-4: advanced-stage PCa before second-line systemic therapies (n = 124).
PSMA-PET in recurrent PCa.
PSMA-PET detection rate was assessed in the overall population and in each subgroup. A multivariable logistic regression model was produced to evaluate the predictors of a positive scan. The performance characteristics of the model were assessed by quantifying the predictive accuracy (PA) according to model calibration. The Youden's index was used to find the best nomogram's cutoff. Decision curve analysis (DCA) was implemented to quantify the nomogram's clinical net benefit.
In the external cohort, the overall detection rate was 53.8% versus 51.2% in the original population. At multivariate analysis, International Society of Urological Pathology grade group, PSA, PSA doubling time, and clinical setting were independent predictors of a positive scan (all p ≤ 0.02). The PA of the nomogram was identical to the original model (82.0%); the model showed an optimal calibration curve. The best nomogram's cutoff was 55%. In the DCA, the nomogram revealed clinical net benefit when the threshold nomogram probabilities were ≥20%. The retrospective design is a major limitation.
The original nomogram exhibited excellent characteristics on external validation. The incidence of a false negative scan can be reduced if PSMA-PET is performed when the predicted probability is ≥20%.
A nomogram has been developed to predict prostate-specific membrane antigen/positron emission tomography (PSMA-PET) results for recurrent prostate cancer (PCa). The nomogram represents an easy tool in the decision-making process of recurrent PCa.
最近开发了一种列线图来预测复发前列腺癌（PCa）患者 Ga 标记的前列腺特异性膜抗原（PSMA）-11 正电子发射断层扫描（PSMA-PET）的结果。
在多中心环境中对原始列线图进行外部验证。
设计、地点和参与者：从六个高容量的 PET 中心回顾性纳入了 1639 名因根治性治疗后前列腺特异性抗原（PSA）复发而行 PSMA-PET 的患者。外部队列根据临床设定类别分层：第 1 组：首次生化复发（n=774）；第 2 组：挽救治疗后 PSA 复发（n=499）；第 3 组：根治性前列腺切除术后生化持续存在（n=210）；第 4 组：二线系统治疗前晚期 PCa（n=124）。
复发 PCa 中的 PSMA-PET。
评估了总体人群和各亚组中的 PSMA-PET 检测率。使用多变量逻辑回归模型评估了阳性扫描的预测因素。通过量化模型校准来评估模型的预测准确性（PA）来评估模型的性能特征。使用约登指数找到最佳列线图的截断值。实施决策曲线分析（DCA）以量化列线图的临床净收益。
在外协队列中，总体检测率为 53.8%，而原始人群为 51.2%。多变量分析显示，国际泌尿病理学会分级组、PSA、PSA 倍增时间和临床设定是阳性扫描的独立预测因素（均 p≤0.02）。该模型的 PA 与原始模型相同（82.0%）；该模型显示出最佳的校准曲线。最佳列线图的截断值为 55%。在 DCA 中，当阈值列线图概率≥20%时，列线图显示出临床净收益。回顾性设计是一个主要的局限性。
原始列线图在外部验证中表现出优异的特征。如果预测概率≥20%时进行 PSMA-PET，则可以降低假阴性扫描的发生率。
已经开发了一种列线图来预测复发性前列腺癌（PCa）的前列腺特异性膜抗原/正电子发射断层扫描（PSMA-PET）结果。该列线图是复发性 PCa 决策过程中的一个简便工具。
