Multiparametric MRI (mpMRI) and prostate-specific membrane antigen (PSMA) PET/CT are complementary imaging modalities used in the presurgical evaluation of patients with prostate cancer (PCa). The purpose of this study was to characterize clinically significant PCa (csPCa) detected and not detected by PSMA PET/CT and mpMRI, focusing on tumors detected solely by PSMA PET/CT and overlooked by mpMRI. Methods: We conducted a single-center, retrospective analysis of patients who underwent both PSMA PET/CT and mpMRI within 3 mo of each other and before radical prostatectomy. Two nuclear medicine physicians and 2 radiologists, in a masked manner, independently contoured PCa lesions on PSMA PET/CT and mpMRI, respectively. A consensus read was done with a third reader for each modality, and a majority rule was applied (2:1). After centralized imaging, a pathologic review was done by a genitourinary pathologist. We assessed agreement between imaging modalities and correlation with pathology. Logistic regression models explored associations between clinicopathologic variables and tumor detection on imaging. Results: In total, 132 csPCa tumors from 100 patients were identified on surgical pathology. PSMA PET/CT showed higher lesion-level (87% vs. 80%) and patient-level (98% vs. 94%) sensitivity than mpMRI. Tumors detected on both imaging modalities were larger and had higher grade groups than those not detected by one or both imaging modalities. On multivariable analysis, csPCa tumors undetected by mpMRI but detected by PSMA PET/CT were smaller than those detected by both modalities. Most tumors showing aggressive pathologic features, such as the large cribriform pattern (94.7%) and the intraductal carcinoma (96%), were correctly detected by both imaging modalities. Limitations included selection bias in a surgical cohort. Conclusion: PSMA PET/CT tends to detect smaller csPCa not detected by mpMRI. Larger tumors on pathology with higher grade groups are more likely to be correctly detected by both imaging modalities. These findings provide insights for refining presurgical evaluation strategies in PCa.

多参数 MRI （mpMRI） 和前列腺特异性膜抗原 （PSMA） PET/CT 是用于前列腺癌 （PCa） 患者术前评估的互补成像方式。本研究的目的是表征 PSMA PET/CT 和 mpMRI 检测和未检测到的具有临床意义的 PCa （csPCa），重点关注仅由 PSMA PET/CT 检测到而被 mpMRI 忽略的肿瘤。方法：我们对在根治性前列腺切除术前 3 个月内同时接受 PSMA PET/CT 和 mpMRI 的患者进行了单中心回顾性分析。两名核医学医师和 2 名放射科医生以蒙面方式，分别在 PSMA PET/CT 和 mpMRI 上独立勾勒 PCa 病灶的轮廓。使用每种模式的第三个读者进行共识读取，并应用多数规则 （2：1）。集中影像学检查后，由泌尿生殖系统病理学家进行病理检查。我们评估了影像学检查方式与病理相关性之间的一致性。Logistic 回归模型探讨了临床病理变量与影像学上肿瘤检测之间的关联。结果：在手术病理学中总共确定了 100 例患者的 132 例 csPCa 肿瘤。PSMA PET/CT 显示比 mpMRI 更高的病灶水平 （87% vs. 80%） 和患者水平 （98% vs. 94%） 敏感性。两种成像方式检测到的肿瘤比一种或两种成像方式未检测到的肿瘤更大，等级更高。在多变量分析中，mpMRI 未检测到但 PSMA PET/CT 检测到的 csPCa 肿瘤小于两种方式检测到的肿瘤。大多数肿瘤表现出侵袭性病理特征，例如大筛状 （94.7%）和导管内癌 （96%），两种成像方式均能正确检测到。局限性包括手术队列中的选择偏倚。结论：PSMA PET/CT 倾向于检测到 mpMRI 未检测到的较小 csPCa。在具有较高级别组的病理学上较大的肿瘤更有可能被两种成像方式正确检测到。这些发现为改进 PCa 的术前评估策略提供了见解。