背景：通过MRI/US融合引导的有针对性活检（TBx）进行精确的风险分层可以指导前列腺癌（PCa）的最佳管理。目标：本研究的目的是比较PI-RADS 2.0版（v2.0）和PI-RADS 2.1版（v2.1）在TBx和根治性前列腺切除术（RP）之间的国际泌尿外科病理学（ISUP）分级升级和降级率。方法：本研究是对从2015年5月到2023年3月期间在一家单一机构进行的前瞻性临床试验中接受3T前列腺MRI的患者进行回顾性事后分析。从试验参与者中选择在1年内接受MRI后连续进行MRI/超声融合引导TBx和RP的患者。一名泌尿生殖系统放射科医师从2015年5月到2019年3月使用PI-RADS v2.0对MRI检查进行临床诠释，从2019年4月到2023年3月使用PI-RADS v2.1。使用卡方检验比较TBx到RP的升级和降级率。临床显著癌症定义为GG≥2。结果：最终分析包括308名患者（中位数年龄为65岁；中位数PSA密度为0.16ng/mL2）。v2.0组（n=177）和v2.1组（n=131）在升级率（29% vs 22%，p=0.15），降级率（19% vs 21%，p=0.76），临床显著升级率（14% vs 10%，p=0.27）和临床显著降级率（1% vs 1%，p>0.99）方面没有显著差异。当按照指标病灶PI-RADS类别或指标病灶区域分层分析时，v2.0组和v2.1组在升级率和降级率上也没有显著差异，仅在没有先前PCa诊断的患者中进行评估（所有p>0.01）。在RP中具有GG2或GG3的患者中（v2.0为121例；v2.1为103例），TBx和RP之间的一致率在v2.0组和v2.1组之间没有显著差异（53% vs 57%，p=0.51）。结论：TBx到RP的升级和降级率在使用v2.0或v2.1进行临床MRI解读的患者中没有显著差异。临床影响：最新的PI-RADS更新的实施并没有改善TBx和手术之间的PCa分级评估不一致。

Background: Precise risk stratification through MRI/US fusion-guided targeted biopsy (TBx) can guide optimal prostate cancer (PCa) management. Objective: The purpose of this study was to compare PI-RADS version 2.0 (v2.0) and PI-RADS version 2.1 (v2.1) in terms of the rates of International Society of Urological Pathology (ISUP) grade group (GG) upgrade and down grade from TBx to radical prostatectomy (RP). Methods: This study entailed a retrospective post-hoc analysis of patients who underwent 3-T prostate MRI at a single institution from May 2015 to March 2023 as part of prospective clinical trials. From the trial participants, those who underwent MRI followed by MRI/ultrasound-fusion guided TBx and RP within a 1-year interval were identified. A single genitourinary radiologist performed clinical interpretations of the MRI examinations using PI-RADS v2.0 from May 2015 to March 2019, and using PI-RADS v2.1 from April 2019 to March 2023. Upgrade and downgrade rates from TBx to RP were compared using chi-square tests. Clinically significant cancer was defined as GG ≥2. Results: The final analysis included 308 patients (median age, 65 years; median PSA density, 0.16 ng/mL2). The v2.0 group (n=177) and v2.1 group (n=131) showed no significant difference in terms of upgrade rate (29% vs 22%, p=.15), downgrade rate (19% vs 21%, p=.76), clinically significant upgrade rate (14% vs 10%, p=.27) or clinically significant downgrade rate (1% vs 1%, p>.99). The upgrade rate and downgrade rate were also not significantly different between the v2.0 and v2.1 groups when stratifying by index lesion PI-RADS category or index lesion zone, as well as when assessed only in patients without a prior PCa diagnosis (all p>.01). Among patients with GG2 or GG3 at RP (n=121 for v2.0; n=103 for v2.1), the concordance rate between TBx and RP was not significantly different between the v2.0 and v2.1 groups (53% vs 57%, p=.51). Conclusion: Upgrade and downgrade rates from TBx to RP were not significantly different between patients whose MRI examinations were clinically interpreted using v2.0 or v2.1. Clinical Impact: Implementation of the most recent PI-RADS update did not improve the incongruence in PCa grade assessment between Tbx and surgery.