If thyroid cancer diagnosis is made directly based on ultrasound alone, misdiagnosis may occur. Of course, an experienced ultrasonographer will judge the disease even at the level of pathological diagnosis. Because ultrasound is not a pathological diagnosis and cannot absolutely diagnose cancer, tumor or benign thyroid nodules directly by ultrasound, even the most experienced doctors may misdiagnose the disease. Therefore, nowadays, the evaluation of thyroid nodules, including breast, is basically based on ultrasound indications, such as thyroid based on the structure of thyroid nodules, whether they are cystic or solid, whether the echogenicity inside is hypoechoic, isoechoic or hyperechoic, whether the morphology of thyroid nodules is The thyroid nodule shape is vertical or horizontal, the aspect ratio is greater than 1 or less than 1, and the boundary is clear or blurred, and there is no calcification inside, such as coarse calcification or microcalcification. Thyroid nodules are scored comprehensively and the nature of the nodule is determined according to the score. Different categories have different risks of malignancy, for example, category I is definitely benign, category II has less than 2% risk, category III has less than 5% risk, category IV has between 5% and 80% risk of malignancy, and category V has more than 20% risk of malignancy. Basically, a comprehensive score is performed according to the indications of nodules seen by ultrasound to determine how many categories the nodules actually belong to, and then the corresponding clinical interventions are taken according to the different categories. Generally speaking, nodules in category 4 require fine needle aspiration (FNA) to confirm the diagnosis. Moreover, fine needle aspiration is related to the level of pathology and aspiration technique and cell volume in the hospital, and there are cases where the results are not available, and sometimes genetic testing or even re-puncture has to be added. For the most common papillary thyroid carcinoma, because the smaller it is, the more typical the image is instead, so at about 2mm, it can be clarified by ultrasound alone, but of course, pathological results are needed eventually.