Radiolabelled prostate-specific membrane antigen (PSMA)-based PET–CT has been shown in numerous studies to be superior to conventional imaging in the detection of nodal or distant metastatic lesions. ⁶⁸Ga-PSMA PET–CT is now recommended by many guidelines for the detection of biochemically relapsed disease after radical local therapy. PSMA radioligands can also function as radiotheranostics, and Lu-PSMA has been shown to be a potential new line of treatment for metastatic castration-resistant prostate cancer. Whole-body (WB) MRI has been shown to have a high diagnostic performance in the detection and monitoring of metastatic bone disease. Prospective, randomized, multicentre studies comparing ⁶⁸Ga-PSMA PET–CT and WB MRI for pelvic nodal and metastatic disease detection are yet to be performed. Challenges for interpretation of PSMA include tracer trapping in non-target tissues and also urinary excretion of tracers, which confounds image interpretation at the vesicoureteral junction. Additionally, studies have shown how long-term androgen deprivation therapy (ADT) affects PSMA expression and could, therefore, reduce tracer uptake and visibility of PSMA⁺ lesions. Furthermore, ADT of short duration might increase PSMA expression, leading to the PSMA flare phenomenon, which makes the accurate monitoring of treatment response to ADT with PSMA PET challenging. Scan duration, detection of incidentalomas and presence of metallic implants are some of the major challenges with WB MRI. Emerging data support the wider adoption of PSMA PET and WB MRI for diagnosis, staging, disease burden evaluation and response monitoring, although their relative roles in the standard-of-care management of patients are yet to be fully defined.

许多研究表明，基于放射性标记的前列腺特异性膜抗原 (PSMA) 的 PET-CT 在检测淋巴结或远处转移性病变方面优于常规成像。⁶⁸ Ga-PSMA PET-CT 现在被许多指南推荐用于检测根治性局部治疗后的生化复发疾病。PSMA 放射配体也可以作为放射治疗剂，Lu-PSMA 已被证明是治疗转移性去势抵抗性前列腺癌的潜在新线。全身 (WB) MRI 已被证明在检测和监测转移性骨病方面具有很高的诊断性能。^比较68项前瞻性、随机、多中心研究用于盆腔淋巴结和转移性疾病检测的 Ga-PSMA PET-CT 和 WB MRI 尚未进行。PSMA 解释的挑战包括示踪剂在非目标组织中的捕获以及示踪剂的尿排泄，这会混淆膀胱输尿管交界处的图像解释。此外，研究表明长期雄激素剥夺疗法 (ADT) 如何影响 PSMA 表达，因此可能会降低示踪剂的摄取和 PSMA ^{+的可见度}病变。此外，短期 ADT 可能会增加 PSMA 表达，导致 PSMA 耀斑现象，这使得 PSMA PET 对 ADT 治疗反应的准确监测具有挑战性。扫描持续时间、偶发瘤的检测和金属植入物的存在是 WB MRI 的一些主要挑战。新兴数据支持更广泛地采用 PSMA PET 和 WB MRI 进行诊断、分期、疾病负担评估和反应监测，尽管它们在患者护理标准管理中的相对作用尚未完全确定。