^99mTc-trofolastat (^99mTc-MIP-1404), a small-molecule inhibitor of prostate-specific membrane antigen, shows high potential to detect prostate cancer (PCa) noninvasively using SPECT. We therefore wanted to assess the performance of ^99mTc-trofolastat SPECT/CT in a phase 2 multicenter, multireader prospective study in patients with intermediate- and high-grade PCa, before radical prostatectomy and extended pelvic lymph node (LN) dissection, with histopathology as the gold standard. Methods: PCa patients (n = 105) with an increased risk of LN involvement (LNI) underwent pelvic ^99mTc-trofolastat SPECT/CT before radical prostatectomy with extended pelvic LN dissection. The sensitivity of ^99mTc-trofolastat for detection of PCa on a patient and lobe basis, using visual and semiquantitative (tumor-to-background ratio [TBR]) scores, and of LNI was evaluated as well as the correlation of uptake within the gland to Gleason scores (GS) and assessment of the predictive potential of ^99mTc-trofolastat uptake for LNI. Results: PCa was detected in 98 patients (94%) with acceptable variability between readers. There was a significantly higher visual score and TBR in positive lobes compared with tumor-negative lobes. Receiver-operating characteristic analysis showed that visual scores more accurately discriminated lobes with GS ≤ 3 + 3 from ≥ 3 + 4, whereas TBRs discriminated high-grade disease from normal lobes better. Visual scores and TBRs correlated significantly with GS. ^99mTc-trofolastat SPECT/CT detected LNI with a sensitivity of 50% and specificity of 87%, and TBR values significantly predicted LNI with a sensitivity of 90%. Conclusion: ^99mTc-trofolastat SPECT/CT detects PCa with high sensitivity in patients with intermediate- and high-risk PCa compared with histology. It has the potential to be used as a surrogate marker for GS and predict LNI.

^99m Tc-曲氟司他（^99m Tc-MIP-1404）是一种前列腺特异性膜抗原的小分子抑制剂，具有使用SPECT无创检测前列腺癌（PCa）的潜力。因此，我们希望通过根治性前列腺切除术和扩大的盆腔淋巴结清扫术，评估^99m Tc-曲氟司他SPECT / CT在中，高级PCa的2期多中心，多读者前瞻性研究中的表现，并进行组织病理学检查作为金标准。方法： PCa患者（n = 105）具有较高的LN受累（LNI）风险，在行根治性前列腺切除术并扩大盆腔LN夹层前行骨盆^99m Tc-曲氟司他SPECT / CT检查。的灵敏度使用视觉和半定量（肿瘤与背景比率[TBR]）评分，使用^99m Tc-曲氟司他在患者和肺叶上检测PCa，并评估LNI以及腺体内摄取与Gleason评分的相关性（GS）和评估^99m Tc-曲氟司他摄取LNI的预测潜力。结果：在98名患者（94％）中检测到PCa，阅读器之间的变异性可以接受。与肿瘤阴性肺叶相比，阳性肺叶的视觉评分和TBR明显更高。接受者操作特征分析表明，视觉评分可以更准确地将GS≤3 + 3的叶与≥3 + 4区分，而TBR可以更好地将高级疾病与正常叶区分开。视觉评分和TBR与GS显着相关。^99m Tc-trofolastat SPECT / CT检测到LNI的敏感性为50％，特异性为87％，TBR值显着预测LNI的敏感性为90％。结论： ^99m与组织学相比，Tc-trofolastat SPECT / CT在中度和高危PCa患者中检测PCa的敏感性较高。它有可能被用作GS的替代标记并预测LNI。