Cancer metastasis can be through blood metastasis, lymphatic metastasis, local implantation metastasis, etc. Among them, lymphatic metastasis is one of the most common metastasis of malignant tumors, and lymph node metastasis is lymphatic metastasis. Generally there will be lymph node enlargement and metastasis in the progressive stage of malignant tumors, because lymphatic system is the immune system of human body, malignant tumors can be phagocytosed by lymphatic system and metastasized through lymph nodes and lymphatic vessels, and at this time, there can be the manifestation of nonspecific lymph node enlargement in different parts of the body. If the tumor is diagnosed as malignant and the lymph nodes have metastasized, surgical treatment, endocrine therapy, chemotherapy, radiotherapy, targeted therapy and so on can be adopted according to the different scope of metastasis. It is recommended to pay attention to the enlarged lymph nodes, diagnose the cause of enlarged lymph nodes as soon as possible, and actively treat the primary disease.