Thyroid cysts are a relatively common thyroid disorder, mainly due to the enlargement of the thyroid gland caused by iodine deficiency, and are a degenerative disease. The majority of thyroid cysts are benign, but a small percentage of thyroid cysts can be associated with thyroid cancer. A thyroid cyst is a cyst that grows in the thyroid gland and is mostly composed of mucus tissue and is not substantial. Depending on the symptoms, thyroid cysts are divided into follicular cysts and nodular cysts. Follicular thyroid cysts are usually associated with inflammatory irritation of the thyroid gland itself, while nodular thyroid cysts are most often caused by hypothyroidism. Patients with thyroid cysts have no systemic symptoms in the early stages, so they are easily overlooked and are often found inadvertently as a swelling in the front of the neck or by chance through a physical examination. However, if left untreated for a long time, a very small number of patients will develop symptoms of hyperthyroidism, and some patients will develop symptoms of reduced thyroid function, such as decreased appetite, weakness, and mild edema. Patients who are detected to have thyroid cysts do not need to be overly nervous and worried, if it is just a simple thyroid cyst and there are no other symptoms, there is no need to do treatment and regular follow-ups are sufficient.