A thyroid nodule graded as grade 4b is considered more likely to be a malignant nodule. It may also appear as a hypodense or very hypodense nodule with irregular margins and no complete envelope, and may have microcalcifications or significant feeding vessels. The thyroid gland should be removed and the lymph nodes in the neck should be cleared. Malignant nodules of the thyroid gland, most commonly papillary and follicular carcinoma, should be diagnosed early and operated on promptly, with regular follow-up and observation after surgery. Malignant tumors of the thyroid gland develop more slowly and require regular postoperative monitoring of thyroid function and long-term treatment with oral thyroxine tablets, also known as eugenol.