Swollen lymph nodes in the neck are a common reason for visits to general surgery clinics. What should patients do when they find swollen lymph nodes in the neck? First of all, do not be anxious. Swollen lymph nodes in the neck are very common, and it is estimated that there are about 300 lymph nodes in the neck, accounting for about 37% of the lymph nodes in the body. Most of them are caused by inflammation, and only a few are related to tumors. Second, visit a hospital and provide your medical history to the clinician who will examine you to see if the lymph nodes are swollen or not (note: some patients may mistake a normal submandibular gland for an enlarged lymph node) and do the necessary tests. Do not start taking antibiotics before you understand what the swollen lymph nodes are all about. There are some swollen lymph nodes for which antibiotics are ineffective, and there is a risk of allergy and masking the condition. After the examination is completed, the clinician will analyze the patient’s condition and examination data together and make a reasonable management. Swollen lymph nodes in the neck can be broadly classified into two categories: one is inflammation and the other is tumor. Inflammation is further divided into general inflammation and specific inflammation. General inflammation includes acute lymphadenitis and chronic lymphadenitis. Acute lymphadenitis is often associated with oral infections, skin infections of the head and face, and upper respiratory tract infections. The manifestations are local lymph node enlargement and pressure pain, local skin congestion and swelling, septic infection is often accompanied by systemic symptoms such as fever, headache, malaise, loss of appetite, and increased percentage of white blood cells and neutrophils in blood routine. For this type of lymph node enlargement, the main treatment is anti-infection, and if localized suppuration occurs, incision and drainage of pus should be performed, while the primary focus of the lymph node infection causing the enlargement should be actively treated. Chronic lymphadenitis is a long-term swelling of lymph nodes caused by chronic infections in the head, neck and oral cavity, mostly manifesting as asymptomatic swelling of lymph nodes in the neck, some of which can have slight local pressure pain. These lymph nodes are mostly soft and mobile when there is no acute inflammation, and once they are transformed into acute inflammation again due to a decrease in systemic resistance, the condition can recur. The enlarged lymph nodes with chronic reactive hyperplasia usually do not need treatment. When acute infection occurs, they can be treated as acute lymphadenitis, and those with recurrent attacks should be carefully searched for the cause and treated reasonably to avoid recurrent attacks. The most common type of cervical specific infection lymphadenitis is cervical lymph node tuberculosis, which commonly occurs in young adults and children, often with a history of tuberculosis or exposure. The enlarged lymph nodes may be solitary or multiple, slowly enlarging, with a medium texture and no significant pain or tenderness. When combined with lymph node necrosis, lymph node softening may occur without general inflammatory manifestations such as redness, swelling, heat and pain. When combined with septic infection, the presentation is similar to that of general septic infection. The treatment of cervical lymphatic tuberculosis is mainly systemic treatment, supplemented by local treatment. When drug therapy is unsatisfactory and local excision is possible, surgical treatment can be considered, and the surgical procedure is tuberculosis lesion removal. In case of combined purulent infection, abscess excision and drainage should be performed. Neoplastic lymph node enlargement is mainly divided into two categories: lymph node metastatic carcinoma and lymphoma. Metastatic cancer of lymph nodes in the neck is caused by metastasis of cancer from organs in the neck or outside the neck. Head and neck lymph nodes mainly receive lymphatic drainage from head and neck organs, but also from the chest, abdomen, pelvis and extremities. The main organs in the head and neck are thyroid, nasopharynx, hypopharynx, larynx, esophagus, etc. In recent years, as the incidence of thyroid cancer is increasing year by year, metastasis to the lymph nodes in the neck due to it is also very common. Metastatic cancer in the neck may appear as single or multiple enlarged lymph nodes with hard texture, and the lymph nodes may fuse and fix in advanced stage. At present, many thyroid cancers are microscopic cancers detected by ultrasound examination during physical examination, lacking clinical symptoms, but the rate of lymph node metastasis is very high. In the last 2 years, the Air Force General Hospital used nano charcoal lymphatic imaging technology in thyroid cancer surgery and found that the lymph node metastasis rate of microscopic cancer was as high as 41.79%. Such metastatic lymph nodes are difficult to be felt by clinicians during physical examination, while ultrasound examination has a greater advantage. The size, structure, shape, whether there is calcification, liquefaction and blood flow of lymph nodes can be observed during ultrasound examination. Therefore, for patients with swollen lymph nodes in the neck, special attention should be paid to the examination of the thyroid gland and whether the swollen lymph nodes in the neck are related to the thyroid gland. For metastatic cancer of the lymph nodes in the neck, the main treatment is for the primary disease. If thyroid cancer is combined with lymph node metastasis in the neck, radical thyroid cancer surgery is performed, along with lymph node dissection in the central region or lateral lymph node dissection. Another type of tumorigenic lymph node enlargement is lymphoma. Lymphoma originates from lymph nodes or other lymphoid tissues and is classified as Hodgkin’s lymphoma or non-Hodgkin’s lymphoma. Non-Hodgkin’s lymphoma has enlarged painless lymph nodes in the neck or supraclavicular region as the first symptom, but may also involve deep (e.g. mediastinum, retroperitoneum) lymph nodes. Since tonsils, nasal cavity and sinuses are the preferred sites, patients may have nasopharyngeal symptoms, and later may have organ compression symptoms such as dysphagia and respiratory distress. Non-Hodgkin’s lymphoma can also involve the gastrointestinal tract, bone marrow and central nervous system, with corresponding signs and symptoms. The gold standard for the diagnosis of lymphoma is pathological diagnosis, including ultrasound-guided lymph node aspiration and lymph node biopsy, the latter of which can obtain intact lymph nodes and is more meaningful for confirming the diagnosis and staging. In addition to the two major types of lymph node enlargement mentioned above, there is also a rare category of lymph node enlargement, such as giant lymph node hyperplasia and necrotizing lymphadenitis, in which giant lymph node hyperplasia can manifest as very large lymph nodes, but is not a tumor. For such lymph node enlargement, it needs to be differentiated from tumors and lymphatic tuberculosis. After analyzing the principles of treatment of causes of enlarged lymph nodes in the neck, it is easy to understand why patients go to the hospital and see the general surgery clinic, but the doctor also recommends consultation in related departments (such as otorhinolaryngology, stomatology, hematology, etc.), based on the fact that there are many causes of enlarged lymph nodes in the neck, and a careful and comprehensive examination and comprehensive analysis are needed to make a correct diagnosis and reasonable treatment.