Thyroid 4a is usually recommended to be punctured first. The risk of malignancy in thyroid 4a nodules is about 2% to 10%, and the management varies according to size and location. Fine needle aspiration biopsy is usually preferred, and if the results are suggestive of malignancy, surgery will be performed. Different sizes of thyroid 4a nodules are treated as follows: 1. Multifocal 4a nodule, or adjacent to the peritoneum, trachea, laryngeal nerve, >10mm, consider ultrasound-guided fine needle aspiration biopsy. 2. Unifocal nodules ≤10mm can be followed up if they are not in the immediate vicinity of the peritoneum, trachea, or recurrent laryngeal nerve. 3. For nodules >15 mm, ultrasound-guided fine-needle aspiration biopsy is recommended. If the ultrasound-guided fine-needle aspiration biopsy result is malignant, surgical resection can be considered. If thyroid 4a nodule is found, it is recommended to consult the doctor in time, improve further examination, and formulate a reasonable treatment plan according to the comprehensive situation under the doctor’s guidance.