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., ADCmin, ADCmean, rADCmin, rADCmean) 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, ADCmin, ADCmean, rADCmin, and rADCmean (all P<0.0001). The Az of the ADCmin (0.956) was greater than that of the other ADC-based criteria and all size-based criteria. Using ADCmin=759.0×10(-6) mm(2)/s, the sensitivity and specificity for differentiating metastatic from non-metastatic lymph nodes were 95.2% and 92.1%, respectively.

Conclusions: DWI, particularly ADCmin, is feasible for differentiating metastatic from non-metastatic pelvic lymph nodes in patients with cervical cancer.