弥散加权磁共振成像对中晚期宫颈癌盆腔和腹腔淋巴结转移的诊断价值

Diagnostic value of diffusion-weighted imaging in pelvic and abdominal lymph node metastases of advanced cervical cancer

目的 :本研究旨在探讨常规磁共振成像(magnetic resonance imaging,MRI)及动态增强扫描加弥散加权成像(dif usion-weighted imaging,DWI)对中晚期宫颈癌盆腔和腹腔淋巴结的显示度以及鉴别良性和恶性淋巴结的诊断价值。方法 :对2011年12月—2012年12月本院收治的80例中晚期宫颈癌患者在同期放化疗前、放疗45 Gy时以及放疗结束后3个月时进行盆腔和腹腔常规MRI及动态增强扫描加DWI,分析感兴趣淋巴结的形态学和功能学参数。结果 :122枚盆腔和腹腔可疑转移淋巴结接受外照射45 Gy和放疗结束后3个月时的最大层面面积明显小于放疗前(P<0.05),T1加权信号变化不明显,T2加权信号不均匀增强;非转移淋巴结放疗前后最大层面面积的变化无统计学意义(P>0.05)。可疑转移淋巴结接受外照射45 Gy和放疗结束后3个月时的DWI MRI表观弥散系数(apparent dif usion coei cient,ADC)明显高于放疗前(P<0.05)。放疗前,可疑转移淋巴结与非转移淋巴结的ADC差异有统计学意义(P>0.05)。结论:盆腔和腹腔常规MRI及动态增强扫描加DWI能够更准确和敏感地显示盆腔和腹腔淋巴结。DWI可以作为淋巴结MRI检查的新手段,有助于鉴别良性和恶性淋巴结。

Objective： To explore the accuracy of routine and dynamic contrast-enhanced magnetic resonance imaging （MRI） and diffusion-weighted imaging （DWl） in detecting pelvic and abdominal lymph nodes （LNs） of patients with advanced cervical cancer and its diagnostic value in distinguishing benign and malignant diseases. Methods： Eighty untreated patients with advanced cervical cancer were collected between December 2011 and December 201 2. Routine and dynamic contrast-enhanced MRI and DWl were performed before concurrent radiochemotherapy, after external radiation of 45 Gy, and three months after the end of radiation therapy. The morphologic and functional parameters of LNs of interest on MRI image were analyzed. Results： The areas of 122 suspected metastatic LNs in pelvic and abdominal cavities on MRI image after external radiation of 45 Gy and three months after the end of radiation therapy were significantly smaller than those before concurrent radiochemotherapy （P 〈 0.05）; the change of T1-weighted signal was not obvious, and T2-weighted signal was heterogeneously enhanced. The areas of non-metastatic LNs were not obviously changed （P 〉 0.05）. The apparent difusion coefficient （ADC） values of 122 suspected metastatic LNs in pelvic and abdominal cavities on MRI image after external radiation of 45 Gy and three months after the end of radiation therapy were significantly increased as compared with that before concurrent radiochemotherapy （P 〈 0.05）. Before concurrent radiochemotherapy,the ADC values were significantly different between suspected metastatic LNs and non-metastatic LNs （P 〉 0.05）. Conclusion： Routine and dynamic contrast-enhanced MRI and DWl can display pelvic and abdominal LNs more accurately and sensitively, and they can help to distinguish benign and malignant diseases.