Comparison between malignant and benign abdominal lymph nodes on diffusion-weighted imaging

Rationale and Objectives. The purpose of this study is to review the apparent diffusion coefficient (ADC) values of benign and metastatic abdominal lymph nodes on diffusion-weighted imaging (DWI). Materials and Methods. Twenty-eight patients with a total of 40 benign (20 patients) and 16 malignant (8 patients) lymph nodes who underwent DWI MRI of the abdomen (b = 0.600) were enrolled in the study. ADC values of the lymph nodes were measured and comparison was made between benign and malignant groups. Results. Mean ADC value of lymph nodes was 2.38 +/- 0.29 and 1.84 +/- 0.37 X 10(-3) mm(2)/sec in the benign and malignant groups, respectively. There was a significant statistical difference between the ADC values of benign and malignant lymph nodes (P < .0005). Conclusion. A wide range of ADC values exist in patients with metastatic abdominal lymph nodes, with a tendency of higher ADC values in benign lymph nodes.