Diagnostic Efficacy of Diffusion-Weighted Magnetic Resonance Imaging (DWI) in the Differentiation of Benign and Malignant Cervical Lymphadenopathies

Pre-operative differentiation of benign from malignant cervical adenopathies remains a challenge. Several studies indicate parameters to discriminate between benign and malignant lymph nodes, which has not yet been enough.

The aim of the current study was to assess the diagnostic efficacy of DWI to differentiate benign from malignant cervical lymph nodes. Patients and

In all patients, we assessed axial and coronal fast spin echo T2 and T1-weighted images and T1-weighted after contrast injection. DWI sequences were implemented before contrast injection, in axial and coronal planes (b factor of 50, 500 and 1000 s/mm2 ) and the apparent diffusion coefficient (ADC) maps were reconstructed. Data were assessed in mixed model analysis and results were compared with postoperative histopathologic findings.

Thirty seven subjects were enrolled, 10 with benign lymphadenopathy and 27 patients with malignant lymphadenopathies before treatment. The mean ADC of the benign neck lymph nodes was (1.00 ± 0.34) × 10-3 mm2 /s, while it was (0.76 ± 0.16) × 10-3 mm2 /s in malignant ones (P = 0.058). The mean ADC of the metastatic nodes was (0.81 ± 0.14) × 10-3 mm2 /s, while it was (0.56 ± 0.04) × 10-3 mm2 /s in lymphoma (P < 0.001). The mean ADC of weakly differentiated metastatic nodes was significantly lower than that of good and moderately differentiated ones [(0.86 ± 0.13) × 10-3 mm2 /s vs. (0.66 ± 0.02) × 10-3 mm2 /s respectively; P = 0.001]. The area under the ROC curve of ADC was 0.69 [95%CI = 0.52 - 0.83]. Considering cut off points of 0.6 × 10-3, 0.95 × 10-3, and 1.2 × 10-3 yielded sensitivities were 15%, 92.5%, and 100%, respectively; while, in these cutoff points, specificities were 80%, 50%, and 40%, respectively.

DWI could be considered as an important diagnostic tool to differentiate enlarged cervical lymphadenopathies.