近期提出的前列腺癌本地复发显像报告系统（PI-RR）旨在推动前列腺癌根治术（RP）和放射疗法（RT）后前列腺癌（PCa）本地复发的磁共振评估的标准化。本研究旨在评估PI-RR的诊断准确性，评估具有不同经验的读片医生之间的一致性，并将成像结果与解剖病理和实验室参数相关联。回顾性纳入了RP或RT后怀疑PCa本地复发的盆腔磁共振成像（October 2017-February 2020）的患者。采用前列腺磁共振图像评分系统由5名具有不同前列腺MRI经验的读片医生独立对每位患者进行评估（两名资深和三名初级放射科医生）。收集生化数据和组织病理特征。通过生化学、成像学或组织病理随访数据确定参考标准。使用列联表评估读片医生的诊断性能。计算Cohen's kappa系数（κ）和组内相关系数（ICC）以评估一致性。最终纳入了120名患者（年龄中位数为72岁[IQR，62-82]）。106名（88.3%）患者的复发得到确认。考虑PI-RR评分≥3作为复发的阳性指标时，读片医生之间的最小和最大诊断指标如下：敏感度79-86％；特异度64-86％；阳性预测值95-98％；阴性预测值33-46％；准确性79-87％。无论读片医生经验水平如何，读片医生之间的一致性良好或极好（所有读片医生之间的κ范围为0.52-0.77），ICC为0.8。前列腺特异性抗原（PSA）速率、基线PSA和触发PSA显示与成像时本地复发有关。PI-RR系统是MRI评估PCa本地复发的有效工具，并促进放射科医生之间的统一性。本研究验证了PI-RR系统对MRI评估PCa本地复发的良好诊断准确性。它显示了具有不同经验水平的读片医生之间的高可重复性，验证了它作为评估生化复发患者的有望标准化工具。在这项回顾性研究中，PI-RR系统在五名不同经验的读片医生中显示出有希望的诊断性能（敏感度79-86％；特异度64-86％；准确性79-87％）。五名读片医生之间的一致性良好或极好（κ范围：0.52-0.77），组内相关系数为0.8。PI-RR评估得分有助于在放射科医生中评估前列腺癌本地复发的标准化和普适性。© 2023作者，欧洲放射学会独家许可使用。

The Prostate Imaging for Recurrence Reporting (PI-RR) system has been recently proposed to promote standardisation in the MR assessment of prostate cancer (PCa) local recurrence after radical prostatectomy (RP) and radiation therapy (RT). This study aims to evaluate PI-RR's diagnostic accuracy, assess the inter-observer reliability among readers with variable experience, and correlate imaging results with anatomopathological and laboratory parameters.Patients who underwent a pelvic MRI for suspicion of PCa local recurrence after RP or RT were retrospectively enrolled (October 2017-February 2020). PI-RR scores were independently assessed for each patient by five readers with variable experience in prostate MRI (two senior and three junior radiologists). Biochemical data and histopathological features were collected. The reference standard was determined through biochemical, imaging, or histopathological follow-up data. Reader's diagnostic performance was assessed using contingency tables. Cohen's kappa coefficient (κ) and intraclass correlation coefficient (ICC) were calculated to measure inter-observer reliability.The final cohort included 120 patients (median age, 72 years [IQR, 62-82]). Recurrence was confirmed in 106 (88.3%) patients. Considering a PI-RR score ≥ 3 as positive for recurrence, minimum and maximum diagnostic values among the readers were as follows: sensitivity 79-86%; specificity 64-86%; positive predictive value 95-98%; negative predictive value 33-46%; accuracy 79-87%. Regardless of reader's level of experience, the inter-observer reliability resulted good or excellent (κ ranges across all readers: 0.52-0.77), and ICC was 0.8. Prostate-specific antigen (PSA) velocity, baseline-PSA, and trigger-PSA resulted predictive of local recurrence at imaging.The PI-RR system is an effective tool for MRI evaluation of PCa local recurrence and facilitates uniformity among radiologists.This study confirmed the PI-RR system's good diagnostic accuracy for the MRI evaluation of PCa local recurrences. It showed high reproducibility among readers with variable experience levels, validating it as a promising standardisation tool for assessing patients with biochemical recurrence.• In this retrospective study, the PI-RR system revealed promising diagnostic performances among five readers with different experience (sensitivity 79-86%; specificity 64-86%; accuracy 79-87%). • The inter-observer reliability among the five readers resulted good or excellent (κ ranges: 0.52-0.77) with an intraclass correlation coefficient of 0.8. • The PI-RR assessment score may facilitate standardisation and generalizability in the evaluation of prostate cancer local recurrence among radiologists.© 2023. The Author(s), under exclusive licence to European Society of Radiology.