Generally, cystic thyroid nodules have low malignancy and do not become cancerous, but in a few cases they may become cancerous, for how long there is no clear clinical data. Cystic thyroid nodules are a type of thyroid nodules, and thyroid nodules can be caused by a variety of causes, such as inflammation of the thyroid gland, degenerative thyroid disease, thyroid hyperplasia, as well as poor dietary habits, environment, genetics or endocrine disorders. Cystic thyroid nodules are usually detected by ultrasound examination of the thyroid gland, and most of them are benign nodules, but the possibility of malignant nodules cannot be ruled out, and fine needle aspiration pathology biopsy can be performed. There are no clear statistics on how long it takes for a cystic nodule to become cancerous. Patients are advised to review and observe regularly, and if they have obvious symptoms of discomfort, they can go to the thyroid surgery department of the hospital as soon as possible. If the pathological examination results highly suspect malignant thyroid nodules, surgery should be taken as soon as possible. Patients are advised not to stay up late at night, to ensure good sleep, and to pay attention to a healthy diet with less barbecue and greasy food and more fresh fruits and vegetables.