Every time I visit the clinic, there are always many patients who walk in with their medical reports and ask anxiously, “I had this checkup and the doctor said I have a thyroid, what should I do?” In fact, everyone has a thyroid gland. The thyroid gland is a very important endocrine organ in our body, located in the lower front of the neck, the main role is to secrete thyroid hormones, responsible for human growth and development, metabolism. To put it simply, the thyroid gland is closely related to how tall and smart children are, and how well adults feel and how hard they work. So, what exactly does the physical examination reveal? It is likely that the doctor found a “thyroid nodule”. Objectively speaking, it is unfair to classify all thyroid nodules as diseases without discrimination. As we age, the thyroid gland, like other organs in the body, undergoes degenerative changes. Just as there are a few gray hairs on your head and a few wrinkles on your face, the thyroid gland will develop some nodules at a certain age, and most of these nodules are benign. Of course, the thyroid gland can also be malignant, so it is important to pay attention to the physical examination, once found abnormalities, should be promptly consulted. Examination: clarifying the nature of nodules So, how do we determine the benignity or malignancy of thyroid nodules? First, according to the development of the disease. Adolescents who develop thyroid nodules need to be alert; middle-aged and elderly people who develop a substantial lump that keeps growing significantly should also be taken seriously. Suddenly growing, smooth, hard, cystic lumps with some swelling and pain are mostly benign. Second, according to the auxiliary examination. The easiest and most effective way to diagnose thyroid nodules is high-frequency color Doppler ultrasound, commonly known as “B-ultrasound,” which not only measures the size of the nodule, but also observes the shape of the nodule. If certain nodules are found, especially substantial nodules with irregular shape, unclear borders, sand-like calcifications and abnormal internal blood supply, further examination is needed. An experienced diagnostic ultrasonographer can determine the nature of a nodule based on its image. Of course, the most direct way to determine the nature of a nodule is by fine needle aspiration cytology. A needle of the same thickness as the needle used to draw blood is inserted into the nodule to be diagnosed, and some thyroid cells are extracted, stained, and then observed under a microscope for cell morphology and structure. Fine needle aspiration not only indicates the benignity or malignancy of the nodule, but also identifies thyroiditis, which is a convenient, economical and minimally invasive diagnostic method. In addition, blood should be drawn to test thyroid function after a thyroid nodule is found. This test not only determines the presence of hyper- or hypothyroidism, but also screens for thyroiditis and allows for early detection of medullary thyroid cancer (a rare but possibly hereditary malignancy of the thyroid gland) by calcitonin measurement. Third, the final diagnosis of the nature of thyroid nodules depends on the “gold standard” of surgical pathology.