Lymph node enlargement is a very common clinical symptom. Generally speaking, the causes of lymph node enlargement vary according to the patients’ primary diseases, which are introduced as follows: a. If the patients have lymph node enlargement due to acute infection, such as liver abscess causing enlarged lymph nodes in the hepatic portal, and septic tonsillitis causing enlarged submandibular lymph nodes. At this time, if the infected lesions can be actively controlled, the enlarged lymph nodes can often be absorbed on their own, and the prognosis is better. If the lymph node enlargement is caused by the invasion of malignant tumor, for example, malignant tumor of the stomach invades the lymph nodes in the lesser curvature of the stomach or the greater curvature of the stomach, causing lymph node enlargement; malignant tumor of the head of the pancreas invades the retroperitoneum, causing lymph node enlargement. In this case, patients need to remove the primary tumor as much as possible, and lymph node dissection combined with systemic chemotherapy and local radiotherapy to kill the tumor cells in the body. Some patients with early disease have relatively good prognosis. Patients with malignant tumors are prone to recurrent disease and cause recurrent lymph node enlargement.