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.