There are two types of thyroid tumors: benign and malignant. Benign tumors can be divided into thyroid adenomas and cysts, while nodular goiter is more common in clinical practice. More than 95% of malignant tumors are primary thyroid cancer, while a very small number of malignant lymphoma and metastases may be present. It occurs mostly in young people, more in women than men, with low malignancy, slow growth, mainly lymph node metastasis, and good healing after surgical treatment. Benign thyroid tumors are very common, and thyroid adenoma accounts for about 50% of the neck lumps. When the tumor is large, it may cause difficulty in breathing, difficulty in swallowing, hoarseness and other symptoms due to compression of trachea, esophagus and nerves, and when the tumor is combined with bleeding and rapidly increasing in size, it may cause local distension and pain. Since benign thyroid tumors may become malignant and some of them are benign but are “hot nodules” (i.e. highly functional), they need to be treated actively. Thyroid adenomas have the potential to cause hyperthyroidism (about 20% of cases) and malignancy (about 10% of cases), so in principle, they should be removed early. If the adenoma is small, adenomectomy alone can be performed, but it should be wedge-shaped, i.e. the adenoma should be surrounded by a small amount of normal thyroid tissue. The excised specimen must be immediately examined by frozen section to determine whether there is malignancy. Thyroid carcinoma is the most common type of malignant tumor in the thyroid gland, and very few of them may have malignant lymphoma and metastases. Except for medullary carcinoma, most thyroid cancers originate from follicular epithelial cells. The incidence of thyroid cancer is related to region, race and gender. According to statistics, the annual incidence of thyroid cancer in the United States increased from 3.6 per 100,000 to 8.7 per 100,000 between 1973 and 2002, a 2.4-fold increase (p<0.001), and the trend is still increasing year by year. The incidence rate of thyroid cancer in China is low, but in Beijing, according to recent statistics, the incidence rate is increasing significantly, which has attracted the attention of medical experts. Papillary carcinoma accounts for about 70% of all adult thyroid cancers. Papillary carcinoma is commonly found in young and middle-aged women, with women aged 21-40 being the most common. This type of carcinoma is well differentiated, slow growing and has low malignancy. It has a tendency to occur multicentrically and may appear early with lymph node metastasis in the neck, so early detection and active treatment are needed for a relatively good prognosis. Surgery is the basic treatment for all types of thyroid cancer except undifferentiated carcinoma, and is complemented by iodine 131 therapy, thyroid hormone and external irradiation. Among malignant tumors, the prognosis of thyroid cancer is generally good. Many thyroid cancers have metastases, but patients can still survive for more than 10 years. There are many factors involved in the prognosis, such as age, gender, pathological type, extent of lesions, metastasis and surgical approach, among which the pathological type is the most important. In particular, papillary carcinoma tends to have good biological characteristics and has the best prognosis, while occult papillary carcinoma has a better prognosis, but a few of them can become undifferentiated carcinoma with very high malignancy; undifferentiated carcinoma has the worst prognosis and patients often die within six months. The larger the size of the tumor, the more chances of infiltration, and the worse its prognosis. According to relevant statistics, the presence or absence of lymph node metastasis does not affect the survival rate of patients. Uncontrolled primary tumor or local recurrence can lead to higher mortality, and the degree of direct tumor spread or infiltration is more important than lymph node metastasis.