When the cyst is smaller than 5cm, minimally invasive treatment can be used. Thyroid cysts are generally benign lesions and rarely become malignant. A thyroid cyst refers to a fluid-containing cystic structure in the thyroid, commonly known as a blister. This blister can be large or small, and is usually asymptomatic when small. For its treatment, when the cyst is smaller than 5cm, a minimally invasive procedure involving fine needle aspiration can be performed to withdraw fluid from the cyst, followed by the injection of anhydrous alcohol to close off the cyst cavity and prevent recurrence. However, if the cyst is larger than 5cm, surgical treatment is recommended for complete removal.