目的：探讨扩散加权成像（DWI）和表观扩散系数（ADC）在诊断前列腺增生和前列腺癌（PCA）中的应用价值。方法：选取2011年05月~2016年05月于我院行穿刺活检或手术病理证实PCA患者42例作为PCA组，同时选取同期经手术证实及临床随访确诊为BPH患者38例作为BPH组，在术前行扩散加权成像检查，b值取800s/mm²，观察比较两组患者DWI和ADC图像，比较PCA未侵犯前列腺组织和BPH前列腺组织ADC值，同时比较PAC外周带癌组织和BPH前列腺组织ADC值。结果：BPH组腺体增生和肌纤维增生在DWI及ADC图分别表现为不均匀高信号和不均匀稍低信号，PCA组DWI为表现高信号，在ADC为低信号。两组患者在正常外周带、腺体增生、间质增生、膀胱、闭孔内肌ADC值比较差异不具有统计学意义。与PCA外周带癌ADC值比较，BPH组增生外周带、中央带腺体增生和中央带肌纤维增生ADC值均显著升高，差异具有统计学意义。结论：DWI和ADC能够对前列腺癌的诊断提供定量诊断信息，应用方便、简单易行，能够作为临床诊断的辅助手段。

 Objective To investigate the application value of diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) in the diagnosis of benign prostatic hyperplasia (BPH) and prostate cancer (PCA). Methods 42 cases of patients with PCA confirmed by biopsy or surgical pathology (PCA group) and 38 cases of patients with BPH confirmed by surgery and follow-up (BPH group) in our hospital from May 2011 to June 2016 were enrolled in the study. DWI was performed before operation, and the b value was 800s/mm². The DWI and ADC images of the two groups were observed and compared. The ADC values of non-PCA invading the prostate tissues and BPH tissues were compared, and ADC values of peripheral carcinoma tissues of PCA and the prostate tissues of BPH were also compared. Results In BPH group, the gland hyperplasia and muscle fiber hyperplasia showed inhomogeneous high signal and inhomogeneous low signal on DWI and ADC images. PCA group showed high signal on DWI and low signal on ADC. There were no significant differences between the two groups in ADC values of normal peripheral zone, glandular hyperplasia, interstitial hyperplasia, bladder and obturator muscle. Compared with the ADC value of PAC peripheral zone, the ADC values of the peripheral zone, the central gland hyperplasia and central muscle fiber hyperplasia of BPH group were significantly higher. Conclusion DWI and ADC can provide quantitative information for the diagnosis of prostate cancer. They are convenient and simple to use, and can be used as assistant tools for clinical diagnosis.