US is a powerful tool for characterization of superficial lymph nodes. Unlike other imaging techniques like CT and MRI, which mainly depend on size for differential diagnosis, US can evaluate important parameters such as shape, margins, internal structure, and abnormal vascularization. It has the advantage of showing early subtle findings of neoplastic involvement like asymmetric thickening and focal lobulations in the cortex, as well as late findings such as diffuse cortical thickening and absence of hilum.