According to U.S. statistics, the incidence of thyroid cancer increased 2.4 times in the 30 years from 1973 to 2003, making it the fastest growing solid tumor, and its mortality rate ranked second among cancer mortality rates. Among them, women are three times more likely to develop thyroid cancer than men. In Tianjin, China, the incidence of thyroid cancer increased by 193% in the 20 years from 1981 to 2001, with a sharp increase in the incidence in women over 60 years of age. The exact causes of thyroid cancer are still inconclusive, but the following factors are recognized: radiation, deterioration of benign thyroid nodules, genetics and diet. Iodine intake is the raw material for synthesizing thyroid hormones, and iodine intake has a close relationship with thyroid disease. Investigation shows that iodine intake and the incidence of thyroid disease show a “U” relationship, that is, too low or too high iodine intake can lead to thyroid disease. Iodine deficiency can lead to goiter and endemic ketosis, while iodine excess can lead to hyperthyroidism and differentiated thyroid cancer. In iodine-rich areas of the world, 5% of women and 1% of men suffer from thyroid nodules, of which 5%-15% are thyroid cancer. About 7% of medullary thyroid cancers have obvious family history and are often combined with pheochromocytoma, so it is presumed that the occurrence of such cancers may be related to chromosomal genetic factors. 3.Radiation damage Research shows that exposure to radioactive substances in the head and neck is an important factor in causing thyroid cancer, such as electrical appliances and CT that we are exposed to in our daily life, all of which will increase the chance of thyroid cancer occurrence. In addition, the incidence of thyroid cancer is significantly higher in women with occupational exposure to ionizing radiation such as X-rays and CT. 4. Other thyroid lesions Clinically, there are reports of thyroid cancer, chronic thyroiditis, nodular goiter or some toxic goiters becoming cancerous, but the relationship between these thyroid lesions and thyroid cancer is not yet certain. For example, most thyroid adenomas are follicular type and only 2% to 5% are papillary; if thyroid cancer is transformed from adenoma, most of them should be follicular type, but in fact, more than half of thyroid cancers are papillary cancers, so it is assumed that the incidence of thyroid adenoma carcinoma is also very small. The incidence rate of thyroid cancer in women is obviously higher than that in men, and the ratio of male to female is 1:3. The higher incidence rate in women may be related to the level of female estrogen. In addition, the increase of thyroid cancer incidence may be related to the popularization of color ultrasound technology, the improvement of ultrasonographers’ examination level and the improvement of the accuracy and sensitivity of the instruments. Prevention: Try not to be exposed to radioactive sources It is difficult to have a clear regulation on iodine intake in the diet, only a balanced nutrition is needed. In addition, low selenium may also lead to thyroid cancer, so it is important to eat more selenium-rich foods, such as fish, shrimp, crab, sesame and garlic. Meanwhile, try not to contact with radioactive sources and be more cautious when doing radioactive treatment. Diagnosis and treatment: Surgery is the first choice Experts say that not all cancers are incurable. Thyroid cancer is the mildest of all malignant tumors, it is not dangerous and develops very slowly. At present, the main methods of detecting thyroid cancer in China are color ultrasound, fine needle aspiration cytology, intraoperative frozen section, CT scan, PET-CT, isotope scan, endoscopy and serological examination. Color ultrasound is the most used and mainstream detection method, with the advantages of being economical, convenient, non-invasive and accurate up to 85%-90%, and is the preferred method for thyroid nodule evaluation. So how to treat thyroid cancer after detection? The most effective and primary treatment for thyroid cancer is surgery; however, a variety of post-operative non-surgical adjuvant treatments are highly relevant to long-term survival. Pharmacological treatment with thyroxine, which is an inhibitory therapy using the negative feedback effect of thyroxine on thyrotropin, can reduce the local recurrence rate and distant metastasis rate of patients. For some tumors that cannot be completely resected, it also has some effect of retarding tumor growth. Isotope therapy also has good efficacy for some thyroid cancers, but it needs to be done after surgery to be most effective. Because of its radioactive nature, it is recommended to be used with caution for patients who are too young. Also, the dose of isotope therapy should be controlled. Interventional treatment is now also available. It is mainly used as an adjuvant, for example, it can be intervened before surgery to create favorable conditions for surgery. Professor Wang Shenming of Zhongshan First Hospital pointed out that, considering all aspects, surgery for thyroid cancer is still the most ideal choice at present, and standardized treatment can make the five-year survival rate of differentiated thyroid cancer reach over 90%. According to the data from the United States, the 20-year survival rate of differentiated thyroid cancer is 24% to 99%. Current surgical methods allow for very inconspicuous scars to meet the patient’s cosmetic needs.