The presence of blood flow signal inside the lymph node suggests that it may be a lymph node with tumor metastasis. In general, normal lymph nodes are oval or fava bean shaped, there is no blood flow signal inside the lymph node, and the lymph node’s cortex and medulla are clearly demarcated, and normal lymph node gates can also be seen. If the lymph nodes appear enlarged, round, and then there is blood flow signal inside the lymph nodes, the lymph node gate disappears, and the demarcation between the cortex and the medulla is not very clear, it is considered that it may be caused by tumor metastasis. If necessary, the enlarged lymph nodes can be completely removed under local anesthesia and sent to pathology for examination, according to the results of the pathology examination, it can be diagnosed whether the enlarged lymph nodes are caused by tumor metastasis.