Lymph Node Characterization by Use of ADC IN NECK MRI

In previous studies, ADC has been evaluated as a possible biomarker of necrotic areas in metastatic cervical lymph nodes from HNSCC [7, 8]. Recently, in two different studies of necrotic cervical nodes, the authors reported that DWI was helpful in distinguishing tuberculous lymphadenitis from malignancy, and suppurative lymphadenitis from malignancy. Zhang et al. [9] found that the mean ADC value for necrosis was higher in the necrotic portions of metastatic nodes (2.02 ± 0.36 × 10−3 mm2 s−1) than in tuberculous nodes (1.25 ± 0.15 × 10−3 mm2 s−1) (p < 0.01). In addition, the optimum ADC threshold for distinguishing between metastasis and tuberculosis was 1.59 × 10−3 mm2 s−1, with sensitivity and specificity of 88 and 100 %, respectively. This was also corroborated in another study by Kato et al. [10] in which the ADC of necrotic cervical nodes was shown to be higher in metastatic nodes (1.46 ± 0.50 × 10−3 mm2 s−1) than in tuberculous nodes (089 ± 0.21 × 10−3 mm2 s−1) (p < 0.01). Thus, ADC could prove useful for identification of metastatic nodes in populations in which granulomatous infections such as tuberculosis are also endemic.