B-mode ultrasound, sono-elastography and diffusion-weighted MRI in differentiation of enlarged axillary lymph nodes in patients with malignant breast disease

Abstract

AimTo evaluate role of B-mode ultrasound, ultrasound elastography and DWI in differentiating benign and malignant axillary lymph nodes. Patients and methodsFrom July 2014 to July 2015, 30 patients with enlarged axillary nodes in patients with malignant breast disease were examined by B mode ultrasound, US elastography and DWI. Finally, findings of B-mode US, elastography and DWI were compared with pathological results (reference standard). ROC analysis was constructed to obtain best cutoff values for B-mode criteria: elasticity score, strain ratio and ADC value. ResultsMean SR of malignant nodes (8.26) was significantly higher than that of benign nodes (2.08) with P value <0.0001. Mean ADC value of malignant nodes (0.7) was significantly lower than mean ADC value of benign nodes (1.4) with P value <0.0001. Comparing results of three imaging modalities showed that DWI had higher sensitivity and accuracy (100%, 96.4%, respectively) than ultrasound elastography (88.89%, 93.33%, respectively) with both modalities which had same specificity (91.67%). Also, DWI and US elastography had higher sensitivity, specificity, accuracy than B-mode ultrasound (77.78%, 66.7%, 73.3% respectively). ConclusionDWI and US elastography significantly aid in improving characterization of metastatic axillary nodes than B-mode US, besides reducing unnecessary invasive biopsy.