Objective: To investigate the effects and value of dynamic contrast-enhanced (DCE) on diffusion-weighted imaging (DWI) score 3 in the prostate imaging data and reporting system version 2(PI-RADS V2)of peripheral zone. Methods: A retrospective study of consecutive 204 cases of prostate disease in peripheral zone was conducted from January 2015 to January 2018, including 169 cases of prostate cancer and 35 cases of non-prostate cancer. All cases were examined multi-parametric MR imaging on a 3-T MR scanner and confirmed by pathology. Images were analyzed according to PI-RADS V2.Inter-reader agreement of scores was evaluated by kappa coefficient. The constituent ratio of clinically significant prostate cancer (csPCa) in PI-RADS V2 overall scores 3, 3+1 and 4 were calculated and analyzed by non-parametric Chi-square test to determine whether the difference in composition ratio was significant. The positive rate of DCE in diffusion weighted imaging (DWI) score 3 and 4 were calculated. Results: There were 68.6%(140/204) cases in 204 patients with peripheral prostate disease who scored PI-RADS V2 overall score of 3,3+1 and 4. Kappa value was higher for the PI-RADS V2 overallscore of 4 than 3 or 3+1 in the PZ (k values of 0.802 vs 0.737 or 0.591, respectively; all P<0.01). The constituent ratio of csPCa in PI-RADS V2 overallscore of 3, 3+1 and 4 were 16.7%(3/18),43.2%(19/44),78.2%(61/78), the difference of which was significant (χ(2)=29.839, P<0.05).There was also a significant difference between the constituent ratio of csPCa in the score of 3+1 and 4 (χ(2)=15.286, P<0.01).The positive rate of DCE in cases of PI-RADS V2 overall score 3,3+1 and 4 was 76.4%(107/140).The positive rate of DCE incases of DWI score 3 and 4 were 71.0%(44/62), 80.8%(63/78),respectively. Conclusion: DCE has a certain value in PI-RADS V2 due to its high positive rate in the detection of prostate cancer in peripheral zone.DCE is helpful to DWI score 3 to improve the detection rate of csPCa.The PI-RADS V2 overall score 3+1 and 4 in the peripheral zone maybe need to be distinguished due to the different detection of csPCa.
目的： 探讨磁共振动态对比增强（DCE）对第2版前列腺影像报告与数据系统（PI-RADS V2）中外周带扩散加权成像（DWI）评分3分的影响和价值。 方法： 回顾性分析2015年1月至2018年1月204例临床疑诊前列腺外周带病变病例（前列腺癌169例，非前列腺癌35例），所有病例均采用Siemens Verio 3.0 T多参数MRI序列扫描并经过病理证实。根据PI-RADS V2评分标准对图像进行评分。通过Kappa系数计算阅片者之间的一致性。计算前列腺临床显著癌（csPCa）在PI-RADS V2总分3分、3+1分、4分中的构成比并通过非参数χ(2)检验分析构成比差异是否有统计学意义，计算DCE在DWI评分3分、4分中的阳性率。 结果： 204例前列腺外周带病变中有68.6%（140/204）的病例评分为PI-RADS V2总分3分比3+1分及4分，PI-RADS V2总分4分的一致性高于PI-RADS V2总分3分及3+1分的一致性（k值0.802 、0.737比0.591,均P<0.01）。csPCa在PI-RADS V2总分3分、3+1分、4分中的构成比分别为16.7%（3/18）、43.2%（19/44）、78.2%（61/78），且构成比差异有统计学意义（χ(2)=29.839, P<0.05），csPCa在PI-RADS V2总分3+1分、4分中的构成比差异有统计学意义（χ(2)=15.286, P<0.01）。DCE在PI-RADS V2总分3分、3+1分、4分的病例中的阳性率为76.4%（107/140例）。DCE在DWI评分为3分、4分的病例中的阳性率分别为71.0%（44/62）、80.8%（63/78）。 结论： DCE在PI-RADS V2中因有较高的阳性率具有一定价值，DCE有助于提高DWI评分3分对csPCa的检出率。外周带中PI-RADS V2总分3+1分与4分因对csPCa的检出率不同而可能需要加以区分。.
Keywords: Gleason score; Magnetic resonance imaging; Prostate imaging reporting and data system; Prostatic neoplasms.