Thyroid swellings are very common, but which ones should be taken seriously? Generally speaking, a solitary thyroid swelling is more likely to be malignant than multiple swellings. A person with a goiter should be alerted to the possibility of a cancerous swelling if he or she has the following manifestations. 1. Children under 14 years of age in non-endemic areas with endemic goiter, if they have a single goiter, 10% to 50% of them are malignant, but most of them are highly differentiated thyroid cancers with a better prognosis; 2. Patients living in the coastal area have a much higher chance of having a single goiter as cancer than those from endemic areas; 3. Single goiter in the thyroid gland of adult males; 4. Goiter that has existed for many years and A single swelling in the thyroid gland is more suspicious in patients who have undergone radiation therapy to the head and neck during childhood; 6. A palpable goiter with a hard texture, irregular fixation or enlarged ipsilateral cervical lymph nodes. If it is accompanied by hoarseness, it suggests that the cancerous nodule may invade the laryngeal nerve; 7. Imaging examination reveals that the calcified shadows in the thyroid gland are cloudy or granular with irregular borders; 8. Ultrasound examination shows solid or cystic solidity with uneven internal echogenicity and unclear and irregular borders; 9. Puncture examination reveals tumor cells.