磁共振扩散加权成像在前列腺癌诊断和鉴别诊断中的价值

Value of diffusion-weighted imaging and apparent diffusion coefficient in the diagnosis and differentialdiagnosis of prostate cancer

目的探讨磁共振扩散加权成像（DWI）和表观弥散系数（ADC）值在前列腺癌诊断与鉴别诊断中的应用价值。方法46例经手术病理或穿刺活检证实的前列腺疾病患者行DWI检查，其中前列腺增生（BPH）21例，慢性前列腺炎9例，前列腺癌16例，扩散敏感分数值800s／mm2。依病理结果，将前列腺外周带六分区归类为正常区、增生区，炎症区、癌区，测量每个分区的ADC值，癌与非癌组之间进行受试者操作特征曲线（ROC）分析。结果各组ADC值分别为，BPH外周带（2．20±0．29）×10-3mm2／s，中央带（1．66±0．14）×10-3 mm2／s，炎症区（1．95±0．34）×10-3 mm2／s，癌区（1．24±0．32）×10-3 mm2／s，组间ADC值两两比较，差异均有统计学意义（均P％0．01）；ROC曲线上临界点取1．49×10-3mm2／s，诊断的敏感性达86．8％，特异性为94．0％，ROC曲线下面积0．945±0．010。结论前列腺DWI及ADC值可用于前列腺肿瘤的诊断和鉴别诊断，具有很高的临床应用价值。

Objective To explore the application of diffusion-weighted imaging （DWI） and apparent diffusion coefficient （ADC） value in the diagnosis and differential diagnosis of prostatic cancer. Methods Diffusion-weighted echo-planar imaging （EPI） sequences were performed in 46 patients, including 21 cases of benign prostatic hyperplasia （BPH）, 9 cases of chronic prostatitis and 16 cases of prostate cancer. DWI were obtained with a b-factor of 800 s/ram2. According to the pathological results obtained by ultrasound guided biopsy, the peripheral zone of prostate was divided into six parts by orientations and they were divided into noncancerous, hyperplasia, prostatitis and cancerous groups. The ADC value of each region was measured and analyzed with one-way ANOVA and ROC analysis. Results Acceptable images for ADC measurement were obtained in all cases. The mean ADC values of prostatic peripheral zone, prostatic central gland, inflammatory area and cancerous area were （2.20±0.29）×10-3 mm2/s, （1.66±0.14）×10-3 mm2/s, （1.95±0.34）×10-3 mm2/s and （1.24±0.32）×10-3 mm2/s, respectively. There were statistically significant differences in ADC values between the inter-groups （P（0.01）. With ROC cut point setting to 1.49×10-3mm2/s, the diagnostic sensitivity and specificity for prostate cancer were 86.8%and 94.0%, the area under the ROC curve （AUC） was 0. 945±0. 010. Conclusions ADC value might be useful to evaluate prostate cancer. DWI has an important clinical application value in the diagnosis and differentiation of prostate cancer.