The incidence of thyroid cancer has continued to rise in the past few years, and thyroid cancer is one of the tumors with the fastest increasing incidence in China. Some regions even rank first in female tumors. This trend exists not only in our country, but also in Korea, Japan, Europe and America, where the incidence of thyroid cancer has increased 3 to 10 times from the 1970s to the present. Researchers at the Mayo Clinic in the United States point out that the incidence of thyroid cancer has increased, but the mortality rate of papillary thyroid cancer has remained stable (0.5 cases per 100,000 in both 1979 and 2009). The rising gap between the two suggests that low-risk cancers are being over-diagnosed and over-treated. Liu Shanting, Department of Head and Neck Thyroid Surgery, Henan Cancer Hospital Sounds scary, but there are several features here: 1. the incidence of thyroid cancer with tumor diameter of 2 cm or more is at the same level as 30 years ago; 2. the mortality rate of thyroid cancer has not changed, still 0.5 per 100,000, 3. the growth cases are dominated by papillary carcinoma; 4. the incidence of undifferentiated thyroid cancer has decreased in the western US. Advances in imaging technology, high technology including ultrasound, CT and MRI imaging techniques can detect very small thyroid nodules, many of which are slow growing papillary thyroid cancers. In addition, as people’s living standards improve with economic development, people are paying more and more attention to their health, and they no longer wait until they have a large neck lump to go to the doctor; instead, they take the initiative to go for medical checkups and discover thyroid nodules of a few millimeters. The increase in the detection rate of thyroid nodules is accompanied by an increase in the detection rate of thyroid cancer, all of which have contributed to the increase in the incidence of thyroid cancer. New technology can detect thyroid nodules as small as 2 mm, many of which are papillary thyroid cancers, the most inert form of thyroid cancer. These thyroid cancers were thought to never cause symptoms and lead to death. But the question arises, what kind of cancer is inert to life? Because some of the micro papillary thyroid cancers can also metastasize early, you can see some patients clinically who even present with enlarged lymph nodes in the neck, and ultrasound can only detect small nodules in the thyroid, while it has metastasized. The color ultrasound TI-RADS grading of thyroid nodules is a diagnostic method proposed in recent years in order to provide an evaluation standard for thyroid nodules. It is based on the ultrasound imaging performance of the thyroid gland to score the nodules, and its evaluation indexes include nodule morphology, boundary, echogenicity, calcification, blood supply, elasticity, etc. After clinical observation, it is a better evaluation method. Ultrasound will TI-RADS grading as follows: Grade 0: no abnormal ultrasound seen in clinically suspected cases, need additional other examinations. grade 1: negative, ultrasound shows gland size, echogenicity can be normal, no nodules, nor cysts or calcifications. grade 2: examination seen benign, risk of malignancy is 0%, all need clinical follow-up. grade 3: probably benign, risk of malignancy is <2%, may need puncture biopsy Grade 4: malignant with a possible percentage of 5 to 50% need to be combined with clinical diagnosis! Grade 5: suggests the greatest likelihood of cancer, <95%. Grade 6: cytologically detectable cancer. When a thyroid nodule has the following sonographic manifestations, the possibility of differentiated thyroid cancer should be considered: (1) Uneven hypoechoic solitary solid nodule with longitudinal diameter larger than transverse diameter, irregular shape, unclear border, no complete envelope and no halo; (2) Nodule with pseudopod, crabfoot-like changes or burr-like protrusion, or enlarged lymph nodes; (3) Nodule with sand-like or rough irregular calcified strong echogenicity and posterior sound attenuation; (4) Nodule with The edges are blurred, and there is high velocity blood flow, increased blood flow signal or disturbed blood flow direction. Some experienced sonographers are able to assess the benignity or malignancy of thyroid nodules preoperatively. When malignancy is indicated, most people are not able to tolerate the pressure and request surgery, even though the cancerous lesions are small. For those who are psychologically fit, microscopic cancer without metastasis can be closely monitored. < p=""> Current technology can only determine the benignity of thyroid nodules, but not which ones are at low risk of never becoming symptomatic or dying. Therefore, a new technique has yet to be developed that can distinguish low-risk micro papillary thyroid cancer and thus prevent this group of patients from receiving unnecessary treatment. At the current state of the art, it requires a joint discussion between the physician and the patient about whether to treat or not.