扩散峰度成像在前列腺癌诊断中的应用价值

The value of diffusion kurtosis imaging in the diagnosis of prostate cancer

目的:探讨扩散峰度成像(DKI)在鉴别前列腺癌与非癌组织(包括良性前列腺增生和正常组织)中的价值。方法:搜集经病理证实的61例前列腺疾病患者的病例资料,包括前列腺癌患者37例(均行前列腺根治切除术)和前列腺增生患者24例(均行经直肠12针穿刺活检)。所有患者均行3.0T常规MRI及10个b值(0、50、100、250、500、750、1000、1500、2000、2500s/mm2)的单次激发EPI扫描,通过DKI模型计算平均扩散系数(MD)和平均峰度(MK)参数图,分别测量前列腺癌组织、中央叶及移行带非癌组织、外周带非癌组织的MD、MK值,比较各组织间的差异,并进行ROC曲线分析,计算MD、MK值诊断前列腺癌的敏感度及特异度。结果:前列腺癌患者的癌组织、中央叶和移行带非癌组织、外周带非癌组织三者之间的MD值、MK值差异均有统计学意义(P<0.001);MD值、MK值在鉴别诊断前列腺癌与非癌组织中具有较高的敏感度和特异度,当MD、MK界值分别为1.617×10^-3mm^2/s、0.736×10^-3mm^2/s时,诊断前列腺癌的敏感度和特异度分别为96.8%、91.6%和95.8%、99.1%,曲线下面积分别为0.993和0.983。结论:DKI模型能较好地反映前列腺癌与非癌组织结构的差异,在前列腺癌诊断中具有较高的临床应用价值。

Objective:To investigate the value of diffusion kurtosis imaging(DKI)in differentiating between cancerous and non-cancerous tissues(including benign prostatic hyperplasia and normal tissues)in prostate cancer.Methods:The clinical data of 61 patients pathologically confirmed with prostate diseases were collected,including 37 patients with prostate cancer(all underwent radical prostatectomy)and 24 patients with benign prostatic hyperplasia(all underwent 12-needle transrectal puncture biopsy).All patients underwent 3.0T routine MRI and single-shot echo planar imaging(EPI)scanning with 10 b values(0,50,100,250,500,750,1000,1500,2000,2500s/mm2).The mean diffusion coefficient(MD)and mean kurtosis(MK)were calculated by DKI model,and the MD and MK values of the cancerous tissues,the non-cancerous tissues in the central lobe&transition zone,and the non-cancerous tissues in the peripheral zone of the prostate were measured.The differences of MD and MK values in those different tissues were compared,and the ROC curves were analyzed to calculate the sensitivity and specificity of MD and MK values in the diagnosis of prostate cancer.Results:There were statistically significant differences in MD and MK values among cancerous tissues,non-cancerous tissues in the central lobe&transition zone and non-cancer tissues in the peripheral zone in prostate cancer patients(P<0.001).The MD and MK value showed high sensitivity and specificity in differentiating cancerous from non-cancer tissues in prostate cancer.When the cut-off value of MD and MK were 1.617×10^-3mm^2/s and 0.736×10^-3mm^2/s,respectively,the sensitivity and specificity in the diagnosis of prostate cancer were 96.8%,91.6%and 95.8%,99.1%,respectively,and the area under the curve were 0.993 and 0.983,respectively.Conclusion:DKI model is capable of reflecting the difference between the cancerous and non-cancer tissues in prostate cancer,and has high clinical application value in the diagnosis of prostate cancer.