With the emphasis on health and the widespread use of ultrasound in thyroid screening, the incidence of thyroid cancer is on a continuous rise. Thyroid cancer is one of the more rapidly increasing incidences of all malignant tumors. At present, thyroid cancer has become one of the solid tumors with the best outcome through the use of comprehensive treatment mainly surgery. Early stage thyroid cancer does not have typical symptoms and signs, so it is not easy to attract patients’ attention. The following points should be taken into consideration: (1) history of radiation exposure, especially those who have received neck radiation treatment during childhood; (2) suspicious ultrasonography; (3) history of thyroid cancer-related diseases: a) pheochromocytoma; b) MEN2; c) familial adenomatous polyposis; d) Carney’s syndrome; e) multiple malignant tumors; (4) thyroid cancer-related diseases; (5) thyroid cancer-related diseases; (6) thyroid cancer-related diseases; (7) thyroid cancer-related diseases; (8) thyroid cancer-related diseases; (9) thyroid cancer-related diseases; (10) thyroid cancer-related diseases; (11) thyroid cancer-related diseases; (12) thyroid cancer-related diseases syndrome; (4) PET-CT detects a localized positive lesion in the thyroid gland; (5) thyroid nodules in children under 14 years of age in non-endemic areas; (6) adult male, solitary nodule in the thyroid gland; (7) isotope scan of a cold nodule is associated with a 10% to 20% likelihood of cancer. (8) A thyroid nodule that has existed for many years and has increased significantly in size in a short period of time. 2. Unintentionally found thyroid nodules with ear, occipital and shoulder pain, hoarseness, difficulty in breathing and swallowing, and in a few cases Horner’s syndrome; in medullary carcinoma, because the tumor itself can produce hormone-like active substances (5-hydroxytryptamine and calcitonin), clinical symptoms such as intractable watery diarrhea, palpitations, flushing of the face and decreased blood calcium can occur. Note the differentiation from the following diseases: 1. Nodular goiter: in endemic areas, dilated follicles integrate into one or several nodules of varying sizes, which may later become locally fibrotic and calcified. May be secondary to hyperthyroidism. 2. Thyroid adenoma: It occurs mostly in women, often under the age of 40. They are usually round or oval-shaped solitary nodules in the thyroid gland; the nodules are soft, smooth, move up and down with swallowing, and grow slowly. Most patients do not feel any discomfort. In some cases, intracapsular hemorrhage occurs, and the tumor size may increase rapidly within a short period of time, resulting in local swelling and pain. 3.Hashimoto’s thyroiditis: Because of the enlarged thyroid gland and hard texture, it can be misdiagnosed as thyroid cancer. This disease occurs mostly in women and has a long course. The enlarged thyroid gland is diffuse and symmetrical with a smooth surface. Thyroid function combined with ultrasound can confirm the diagnosis; the gland can often shrink significantly after treatment with levothyroxine.