Role of Color Doppler Ultrasound in Differentiation Between Benign and Malignant Lymphadenopathy

Various ultrasound criteria that can help in differentiation of benign and malignant lymph nodes have been well described in literature. On Gray scale ultrasound imaging, the benign enlarged lymph nodes are hypoechoic, oval shaped with smooth border and echogenic hilum. On the other hand, the malignant lymph nodes are round with short to long axis ratio >0.5 and show loss of echogenic hilum, while the Color and Power Doppler features documented for the diagnosis of malignant lymph nodes are peripheral and mixed vascularity, with resistive index (RI) more than 0.8, and pulsatility index (PI) more than 1.5 Although Color Doppler ultrasound improves diagnostic accuracy and plays an important adjuvant role to Gray scale ultrasound in differentiating benign from malignant lymph nodes as it adds to the diagnostic confidence of predicting malignancy in enlarged lymph nodes, and also is useful if Gray scale ultrasound findings are equivocal. However, it can neither replace histopathology nor can eliminate the need for biopsy