Necrotic cervical nodes: Usefulness of diffusion-weighted MR imaging in the differentiation of suppurative lymphadenitis from malignancy

Purpose: The purpose of this study was to assess the efficacy of diffusion-weighted (DW) MR imaging for the differentiation between suppurative lymphadenitis and malignancy in necrotic cervical lymph nodes. Materials and methods: Fifteen patients with suppurative lymphadenitis, 40 with squamous cell carcinoma (SCC), eight with lymphoma, and six with thyroid cancer were accompanied by necrotic cervical nodes. All 69 patients underwent 1.5-T MR imaging including DW and 58 underwent gadolinium-enhanced MR imaging. Necrotic area-to-spinal cord signal intensity ratios (SIR) on T1-, T2- and DW images and apparent diffusion coefficients (ADCs) [10(-3) mm(2)/s] were correlated with the pathologies. Results: Nineteen necrotic cervical nodes with suppurative lymphadenitis, 67 with SCC, 10 with lymphoma, and 12 with thyroid cancer were identified. SIR on DW images was higher in suppurative lymphadenitis (2.50 +/- 1.21) than in malignancies (1.29 +/- 0.67) (p < .01), and ADC value was lower in suppurative lymphadenitis (0.89 +/- 0.21) than in malignancies (1.46 +/- 0.46) (p < .01). SIR on T1-weighted images was higher in thyroid cancer (1.95 +/- 0.53) than in suppurative lymphadenitis (0.87 +/- 0.17), SCC (0.92 +/- 0.13), and lymphoma (0.95 +/- 0.09) (p < .01). No significant difference in SIR on T2-weighted images was found between suppurative lymphadenitis (1.46 +/- 0.50) and malignancies (1.61 +/- 0.56). Conclusion: DW imaging with ADC measurements may play a supplementary role in the differentiation of necrotic cervical nodes between suppurative lymphadenitis and malignancy. (C) 2012 Elsevier Ireland Ltd. All rights reserved.