3.0T磁共振扩散加权成像在经直肠超声引导前列腺穿刺活组织检查中的价值

The role of 3.0T magnetic resonance diffusion-weighted imaging in transrectal ultrasound guided prostate biopsy

目的探讨综合经直肠超声(TRUS)和磁共振成像(MRI)的穿刺方案对前列腺癌患者阳性检出率的影响,以及TRUS和MRI对穿刺选点的价值。方法 80例前列腺癌疑似患者在穿刺活组织检查前行TRUS和MRI检查。穿刺以8点法系统穿刺为基础,再对影像学检查可疑区行靶向穿刺,将影像学检查结果与病理检查结果进行对照。结果 8点法系统穿刺结合TRUS目标靶向穿刺的阳性率为33.8%(27/80),增加MRI目标靶向穿刺后的阳性率为45.0%(36/80),增加MRI目标靶向穿刺活组织检查的诊断阳性率较8点法系统穿刺结合TRUS目标靶向穿刺诊断阳性率有升高的趋势,但差异无统计学意义(P>0.05)。按穿刺点位分析,TRUS、MRI单独应用对前列腺癌诊断的敏感度、特异度、阳性预测值、阴性预测值和准确率的差异均无统计学意义(P值均>0.05);TRUS与MRI联合应用对前列腺癌诊断的敏感度、阳性预测值、准确率均显著高于TRUS、MRI单独应用(P值均<0.05)。TRUS、MRI检查对前列腺疾病诊断结果具有中等程度的一致性,Kappa值为0.58。结论增加MRI目标靶向穿刺后,前列腺癌的检出率有升高趋势。MRI和TRUS对不同部位前列腺癌灶的诊断存在互补性。

Objective To evaluate the value of combination of transrectal ultrasound （TRUS） and magnetic resonance imaging （MRI） for the diagnosis of prostate cancer and the effect of TRUS and MRI on prostate biopsy. Methods Eighty patients with elevated prostate specific antigen or abnormal digital rectal examination were enrolled in this study. TRUS and MRI were performed before biopsy. Then systematic octant biopsy, TRUS targeted biopsy and MRI targeted biopsy were performed. The results of TRUS and MRI were compared with pathological examination. Results The detection rate of prostate cancer was 33.8% （27/80） when applying systematic octant biopsy in combination with TRUS targeted biopsy. The detection rate was increased by 45.0 % （36/80） when additionally using targeted biopsy of MRI suspicious areas, but the difference was not statistically significant （P〉0.05）. Based on biopsy cores, there were no significant differences in terms of the sensitivity, specificity, positive prediction, negative prediction, or accuracy between TRUS and MRI （P〉0.05）. After combination of TRUS and MRI, the sensitivity, positive prediction and accuracy of prostate cancer were significantly higher than TRUS or MRI alone （P〈0.05）. The accuracy of TRUS was moderately consistent with MRI （Kappa= 0.58）. Conclusion The detection rate of prostate cancer tends to increase after additionally applying targeted biopsy of MRI suspicious areas. MRI and TRUS are complementary methods in diagnosis of prostate lesions. （Shanghai Med J, 2013, 36： 243-247）