弥散加权成像对宫颈癌淋巴结转移的诊断价值

目的 探讨弥散加权成像(DWI)对宫颈癌转移及非转移淋巴结的诊断价值。方法 回顾性收集经手术病理证实的行淋巴结清扫的宫颈癌患者65例,所有患者均在术前行盆腔常规MRI及DWI检查。手术共切除淋巴结1590枚,将短径≥5 mm的392枚淋巴结纳入本研究。测量淋巴结的长径(L)、短径(S)及表观弥散系数ADC_min、ADC_mean和原发癌灶的ADC_min、ADC_mean,计算淋巴结的S/L、rADC_min、rADC_mean,比较转移及非转移淋巴结的形态学指标及ADC值差异。结果 转移淋巴结的L、S、S/L均显著大于非转移淋巴结(P均＜0.0001),转移淋巴结的ADC_min、ADC_mean、rADC_min、rADC_mean均显著小于非转移淋巴结(P均＜0.0001);ADC_min鉴别转移及非转移淋巴结的Az(0.956)最大,高于其他ADC值及形态学指标;以ADC_min=759.0×10^-6 mm²/s作为鉴别淋巴结转移的阈值,敏感性和特异性分别为95.2%和92.1%。结论 DWI尤其ADC_min有助于鉴别宫颈癌转移及非转移淋巴结。

Value of Diffusion-weighted Imaging in Diagnosis of Lymph Node Metastasis in Patients with Cervical Cancer

Objective To investigate the value of diffusion-weighted imaging(DWI)in the differentiation of metastatic lymph nodes from non-metastatic lymph nodes in cervical cancer.Methods In 65 patients who underwent lymph node dissection for cervical cancer,conventional MRI and DWI examinations were performed before surgery.Of the 1590 total dissected pelvic lymph nodes,392 enlarged nodes with a short-axis diameter(S)of 5 mm or greater were included for further analysis.Each of the size-based criteria[i.e.,S,long-axis diameter(L),and S/L ratio]and apparent diffusion coefficient(ADC)-based criteria(i.e.,ADC_min,ADC_mean,rADC_min,rADC_mean)were compared between metastatic lymph nodes and non-metastatic lymph nodes.Results There were statistically significant differences between metastatic and non-metastatic lymph nodes in S,L,S/L ratio,ADC_min,ADC_mean,rADC_min ,and rADC_mean(all P＜0.0001).The Az of the ADC_min(0.956)was greater than that of the other ADC-based criteria and all size-based criteria.Using ADC_min=759.0×10^-6 mm²/s,the sensitivity and specificity for differentiating metastatic from non-metastatic lymph nodes were 95.2% and 92.1%,respectively.Conclusion DWI,particularly ADC_min,is feasible for differentiating metastatic from non-metastatic pelvic lymph nodes in patients with cervical cancer.