Lymphatic metastasis mainly refers to patients with malignant tumors in which cancer cells spread with lymphatic vessels as the disease progresses. Lymphatic metastasis can be detected through physical examination, imaging examination and pathological examination. 1. Physical examination: when lymphatic metastasis occurs in the primary tumor, the lymph nodes in the corresponding metastatic site may be enlarged. For example, breast cancer patients may have lymph node metastasis in the axilla and supraclavicular lymph nodes of the same side, resulting in enlargement of the lymph nodes there. On palpation, painless enlarged lymph nodes can be found, which are hard in texture and usually have no tenderness. 2. Imaging examination: for superficial lymph nodes, besides palpation, relevant imaging examination can also be given. For example, color ultrasound examination, etc., for the chest cavity, abdominal cavity and other deep lymph nodes examination, need to also be given to the CT, MRI, PET-CT and other examinations, can be found in the body of the lymph nodes enlarged or fusion. 3. Pathological examination: for those who have enlarged lymph nodes or suspect the existence of lymphatic metastasis, puncture biopsy of lymph nodes can be performed and pathological examination can be determined. It is recommended to go to the hospital in order to have a clear diagnosis and treatment.