宫颈癌转移性淋巴结的CT影像学特点

CT image characteristics of metastatic lymph nodes in cervical cancer

目的探讨多层螺旋CT(MSCT)应用于宫颈癌淋巴结转移术前诊断的最佳形态学标准。方法纳入2009年1月～2012年8月于眉山市人民医院妇产科住院的原发宫颈癌患者100例。使用64排MSCT行全盆腔增强扫描测量患者局域淋巴结的最大短轴、最大长轴以及轴径比(最大短轴/最大长轴)。采用不同形态学标准进行MSCT术前N分期,并与术后病理分期比较,分析各形态学标准的诊断价值。结果转移性和非转移性淋巴结在影像学特点上没有统计学差异。采用短轴直径6 mm的ROC曲线面积大于其长度,差异有统计学意义(P<0.05);采用轴径比=0.9的ROC曲线面积大于其长度,差异有统计学意义(P<0.05)。以最大短轴≥6 mm诊断为转移性淋巴结时,敏感度为63.6%,特异度为66.7%,准确度为65.0%,阳性预测值为70.0%,阴性预测值为62.3%;以轴径比=0.9为分界点时,敏感度为16.5%,特异度为79.8%,准确度为41.0%,阳性预测值为57.6%,阴性预测值为36.6%。结论推荐短轴≥6 mm作为转移性淋巴结的最佳诊断标准,并可结合轴径比(0.9)对转移性淋巴结肿大进行鉴别诊断以提高特异度。

Objective To investigate the most optimal morphological criteria of metastatic lymph node in cervical can cer.Methods 100 patients with cervical carcinoma were enrolled from January 2009 to August 2012 in People＇s Hos pital of Meishan City.The abdomen of patients were scanned by 64-multi-slice spiral computer tomography preopera tively,and the maximal long-axis diameter,maximal short-axis diameter,axial ratio were measured.Different morpho logic criterion were used to diagnose the metastatic lymph nodes.Results The difference of image characteristics between metastatic and non-metastatic lymph nodes were not statistically significant.The AUC of 6 mm diameter（short axis） and axial ratio（0.9） were significantly bigger than the lengths,respectively（P〈0.05）.The cut-off value of lymph nodes diameter for diagnosing metastasis was 6 mm（short axis）,with the sensitivity of 63.6%,specificity of 66.7%,ac curacy of 65.0%,positive predictive value（PPV） of 70.0%,negative predictive value（NPV） of 62.3%,respectively.Meanwhile,the cut-off of axial ratio was 0.9,with the sensitivity of 16.5%,specificity of 79.8%,accuracy of 41.0%,PPV of 57.6%,NPV of 36.6%,respectively.Conclusion Short axis diameter of lymph node ≥ 6 mm,combined with axis ratio（0.9）,may be the good diagnostic criterion for lymphatic metastasis.