The thyroid gland is located in the anterior middle region of the neck, below the laryngeal node, and is divided into two lobes, left and right, on either side of the trachea in the neck. The normal thyroid gland is invisible and can be faintly touched and moved up and down with swallowing. Once enlarged or lumpy, it may appear as a protrusion in the area equivalent to the collar. The thyroid gland plays an important role in human metabolism and growth and development. Thyroid cancer is a common malignant tumor of the head and neck, accounting for 1% to 3% of all malignant tumors in the body. It can occur at any age, mostly between 21 and 50 years old, but most of the female patients are young people under 25 years old. Risk factors 1. Hyperplastic thyroid disease can be combined with thyroid cancer, such as endemic goiter endemic areas, where the incidence of thyroid cancer is higher. 2.Radiation damage: It is documented that those who have received radiation exposure during infancy and childhood due to benign diseases are the predisposing factors for thyroid cancer in young people; in addition, those who are exposed to atomic radiation and those who receive radionuclide iodine treatment are prone to thyroid cancer. 3. Benign thyroid diseases: such as thyroid tumor, goiter, lymphatic thyroiditis, etc., all have the possibility of cancer. For example, the cancer rate of simple goiter is 20%, and the cancer rate of hyperthyroidism is 2%. 4.Endocrine factors: Long-term endocrine disorder may cause mutation of thyroid cells and develop into cancer. 5.Iodine deficiency: Anti-thyroid drugs and unilateral thyroid gland lobectomy can lead to thyroid cancer. 6.Sex hormone: it may be a factor of thyroid cancer 3.Abnormal manifestation It may manifest as similar benign lesion or hard mass of infiltrative nature, with symptoms such as hoarseness and dyspnea 1.Papillary adenoma is usually found in 40 years old women, with irregular shape, hard, with certain mobility and slow growth, which can be up to 5~20 years. Patients mostly have no obvious discomfort, but invasion of trachea and surrounding soft tissues may lead to dyspnea, hemoptysis, swallowing discomfort, etc. When the recurrent laryngeal nerve is involved, hoarseness may appear, and 50%-70% of patients have neck lumps at the initial diagnosis. 2. Follicular carcinoma is mostly seen in middle-aged and elderly women aged 40-60 years old, with slow growth and mostly solitary. The edges of the mass are clear and can move with swallowing. Lymph node metastasis is rare, and it mostly metastasizes to lung and bone with blood flow. Medullary carcinoma is slow growing, hard in texture, familial, accounting for 5% to 10% of the disease. 20% to 30% of patients have facial flushing, persistent diarrhea, watery stool, and diarrhea stops after lesion removal, but it will appear again if it recurs or metastasizes. 4.Undifferentiated carcinoma is predominant in elderly people. It is manifested as a sudden enlargement of a multi-year thyroid mass or nodule with rapid growth, hard and fixed, which may cause hoarseness, breathing difficulty, eating disorder and pain in the neck and ear area, and is often accompanied by enlarged submandibular lymph nodes. Prevention and rehabilitation 1. Any masses found in the front of the neck, in front of the trachea and on both sides of the trachea should be examined in a specialized oncology hospital. 2. Carry out cancer prevention screening and actively treat solitary thyroid nodules. Residents in areas with a high incidence of simple goiter should pay attention to scientific dietary adjustment, use iodized salt, and take appropriate amounts of thyroxine supplements to inhibit thyroid tissue proliferation. 4. Actively prevent and treat benign thyroid diseases, such as simple goiter and hyperthyroidism. 5.Emotional optimism, avoid long-term adverse stimulation, and maintain normal endocrine function. 6.Avoid head and neck X-ray exposure during childhood as much as possible. 7.Regular review: thyroid cancer recurrence mostly occurs several years after surgery, attention should be paid to regular review and frequent self-examination to detect metastatic signals in time. 8.After thyroid cancer surgery, thyroxine tablets should be taken for a long time to treat and prevent recurrence of the disease because thyroxine can inhibit the secretion of thyroxine by the pituitary gland, thus inhibiting the proliferation of thyroid tissue and the development of the disease. Be sure to take the medication on time. V. Prognosis Thyroid cancer is a special disease different from cancer in other parts of the body and has its own unique clinical characteristics, with more female patients, more young ones and relatively good prognosis (except for undifferentiated cancer). Especially for young women with papillary carcinoma, most of them can be cured if treated timely. The literature reports that the 5-year survival rate of early thyroid cancer can reach more than 90%.