Thyroid nodules are clumps of tissue that appear in the thyroid tissue after an abnormal proliferation of thyroid cells. It can be seen in benign nodules, or may be thyroid cancer and other lesions. 1. Simple benign nodules: most patients have simple thyroid nodules with clear boundaries and slow growth, which can be asymptomatic, while a few patients with large nodules may have hoarseness, difficulty in breathing and swallowing, etc., when the nodules are compressing the surrounding tissues. 2. Benign nodules with hyperthyroidism: some patients may have hyperthyroidism, which may be characterized by fear of heat and excessive sweating, anxiety and irritability, palpitation and shortness of breath, increased frequency of defecation, weight loss, and protruding eyes. 3. Thyroid cancer: the boundary of the nodule is not clear, can be infiltrative growth, and invade the neighboring tissues, resulting in breathing and swallowing difficulties, hoarse voice and other symptoms. The diagnosis can be confirmed by puncture biopsy. Most of the thyroid nodules have a good prognosis, but some of them may become cancerous, so they should be actively followed up and reviewed under the guidance of doctors for timely treatment.