Fig. 2

A metastatic cervical small lymph node of a 30-year-old man with nasopharyngeal carcinoma. a Axial T2-weighted MR image reveals an 8.0 × 10.0-mm-sized lymph node in the left level IIb area (green arrow). b Appearance in Conventional high-frequency ultrasonography B mode with displacement of hilum, heterogeneous internal echogenicity and irregular margins. c Abnormal peripheral vascularization is seen in color Doppler. d Shear wave elastography reveals markedly heterogeneous color equating to very high and low stiffness in the node. Shear elasticity indices of the stiffest region were measured by one 3-mm diameter Q-box. e Ultrasound guided core needle biopsy of the targeted stiffest area of sLN revealed by shear wave elastography. White triangles showed the needle. Green arrow showed the targeted small lymph node. f Hematoxylin and eosin staining (magnification 100×) of the core needle biopsy sample showed that metastasis from nasopharyngeal carcinoma in the lymph node, which was confirmed by immune-histo-chemistry