Thyroid cancer accounts for about 1% of all cancers, while thyroid nodules account for about 5% of thyroid cancers. The incidence rate of thyroid cancer in men is less than 3/100,000 per year, while in women it is 2-3 times higher. The age distribution of various types of thyroid cancer varies, with papillary carcinoma being the most widely distributed, follicular carcinoma being most common between 20 and 100 years old, medullary carcinoma between 40 and 80 years old, and undifferentiated carcinoma between 40 and 90 years old. Clinical manifestations The diagnosis of thyroid cancer is early. Any isolated thyroid nodules found should be clinically excluded from thyroid cancer. If the nodule is hard and uneven, accompanied by enlarged cervical lymph nodes, paralysis of the recurrent laryngeal nerve or previous history of neck reflexes, the possibility of cancer is high. Similarly, if one of the multiple nodules in the thyroid gland is particularly prominent and hard, thyroid cancer should be suspected. In addition, if the thyroid gland itself appears asymmetrically enlarged or hard nodules that are rapidly increasing or fixed, thyroid cancer should be considered as a possibility. Ultrasound examination of the thyroid gland is still the most basic and important test. 131Ⅰ or 99mTc thyroid scan can only reflect the morphology of the nodule and its isotope uptake function, but cannot determine its nature. If the above tests cannot confirm the diagnosis, fine needle aspiration cytology is feasible and should be performed 1 day before surgery, with a high diagnostic compliance rate. In 10% of cases, no further cellular classification can be made, so surgical exploration and histological examination are still required. Patients with the following manifestations should be alerted to the possibility of cancerous nodules (1) In non-endemic areas of endemic goiter, a single thyroid nodule in children under 14 years of age, 10% to 50% of which are malignant. However, all are well-differentiated thyroid carcinomas. (2) A single nodule in the thyroid gland of an adult male. (3) A thyroid nodule that has existed for many years and has increased significantly in size in a short period of time. (4) Patients with coastal residence have a much higher chance of having a single nodule as cancer than those from endemic goiter areas. (5) A single nodule in the thyroid gland is more suspicious in patients who have received radiation therapy to the head and neck during childhood. (6) The nodule is firm, irregularly fixed or with enlarged ipsilateral cervical lymph nodes. Vocal cord paralysis. (7) Neck radiograph shows cloudy or granular shadows of calcification in the thyroid gland. The border is irregular. The tracheal stenosis caused by thyroid cancer is often normal in left and right diameter, and anterior and posterior diameter can be normal. (8) Ultrasound examination shows solid or cystic solidity with uneven internal echogenicity and unclear and irregular borders. (9) Tumor cells are found on puncture examination, and the aspiration fluid may gradually turn dark red for cystic masses, which is a characteristic of metastatic foci of papillary thyroid adenocarcinoma. Treatment is mainly surgery and postoperative radiotherapy.