前列腺特异性膜抗原正电子发射断层扫描在达到凤凰标准之前检测前列腺癌生化复发：早期发现复发

前列腺癌（PCa）在根治性放疗（RT）后发生的生化复发（BCR），依据凤凰标准定义为PSA最低值之上升≥2.0 ng/ml的PSA升高。基于前列腺特异性膜抗原（PSMA）的正电子发射断层扫描/计算机断层扫描（PET/CT）可以在极低的PSA值下检测到PCa的复发。我们的目标是研究在根治性放疗后，使用PSMA PET/CT检测PCa复发的检出率和范围，特别是在PSA升高≥2.0 ng/ml（凤凰阳性，Ph+）和未达到此阈值（凤凰阴性，Ph-）的患者中，并比较治疗管理方案、以及在激素剥夺治疗（ADT）和去势抵抗性前列腺癌（CRPC）方面的临床结局，包括总生存期。我们对2015-2023年间荷兰前列腺癌网络（Prostate Cancer Network Amsterdam）包含的568例接受根治性放疗的PCa患者进行了回顾性分析。收集了PSMA PET/CT结果、治疗管理和临床随访数据，包括（再）启动ADT、CRPC进展及生存情况。通过逻辑回归和生存分析比较不同组别的结果。研究队列中，222例患者（39.1%）为Ph-，346例（60.9%）为Ph+。在这两组中，分别在170例Ph-患者（76.6%）和322例Ph+患者（93.1%）中检测到PSMA显像阳性病灶。两组中，75.9%的Ph-患者和45.0%的Ph+患者符合局部挽救治疗的条件（比值比[OR] 3.84；p < 0.001）。远处转移在Ph-组（37例，占21.8%）中较少见，明显低于Ph+组（157例，占48.8%；OR 0.29；p < 0.001）。生存分析显示，Ph-组在ADT（再）启动和CRPC进展的时间上更长，总体死亡率也更低（log-rank p < 0.001）。本研究的主要局限性为其回顾性设计。对于前列腺癌复发的患者，PSMA PET/CT能够在大多数未达到凤凰标准的病例中检测到复发，早期成像有助于在疾病较早阶段发现复发，从而为潜在的挽救性治疗提供可能。此外，早期PSMA PET/CT的应用与延长ADT（再）启动和CRPC进展的时间、提高总体生存期相关。这些积极的临床意义有待在前瞻性研究中得到验证，以减少潜在的提前诊断偏倚。我们研究了在放疗后疑似复发的前列腺癌患者中，早期应用一种特殊扫描技术——PSMA PET（前列腺特异性膜抗原正电子发射断层扫描）的效果。早期扫描可以在癌症进展到更晚阶段之前检测到复发。

Biochemical recurrence (BCR) of prostate cancer (PCa) after curative radiotherapy (RT) is defined according to the Phoenix criteria, which is a prostate-specific antigen (PSA) rise of ≥2.0 ng/ml above the PSA nadir. Prostate-specific membrane antigen (PSMA)-based positron emission tomography/computed tomography (PET/CT) can identify PCa recurrences at very low PSA values. Our aim was to investigate the detection rate and extent of PCa recurrences using PSMA PET/CT after curative RT among patients with a PSA rise of ≥2.0 ng/ml above the nadir (Phoenix positive, Ph+) and patients not reaching this threshold (Phoenix negative, Ph-) and to compare therapeutic management and clinical outcomes in terms of time to androgen deprivation therapy (ADT) and castration-resistance PCa (CRPC), as well as overall survival.We conducted a retrospective analysis of the Prostate Cancer Network Amsterdam (2015-2023) cohort of 568 patients who received curative-intent RT for PCa. Data on PSMA PET/CT outcomes, therapeutic management, and clinical follow-up were collected, including (re)initiation of ADT, progression to CRPC, and survival. Results were compared between groups using logistic regression and survival analyses.The study cohort comprised 222 patients (39.1%) classified as Ph- and 346 (60.9%) classified as Ph+. PSMA-avid lesions were detected in 170 Ph- patients (76.6%) and 322 (93.1%) Ph+ patients. In these groups, 75.9% of Ph- patients and 45.0% of Ph+ patients were eligible for local salvage therapy (odds ratio [OR 3.84]; p < 0.001). Distant metastases were less frequent in the Ph- group (n = 37, 21.8%) than in the Ph+ group (n = 157, 48.8%; OR 0.29; p < 0.001). Survival analyses revealed longer times to ADT (re)initiation and progression to CRPC, as well as lower overall mortality, in the Ph- group (log-rank p < 0.001). The retrospective study design is the main limitation.For patients with PCa recurrence, PSMA PET/CT can detect this recurrence in the majority of cases not meeting the Phoenix criteria for BCR. Early imaging detects recurrences at a less advanced disease stage, allowing potential salvage treatments. In addition, early PSMA PET/CT is associated with longer times to ADT (re)initiation and progression to CRPC, as well as longer overall survival. These positive clinical implications warrant confirmation of our results in prospective studies to reduce potential leadtime bias.We investigated early use of a special type of scan called PSMA PET (prostate-specific membrane antigen positron emission tomography) in patients with suspicion of recurrence of their prostate cancer after radiotherapy. Early scans can detect recurrence before the cancer progresses to a more advanced stage.