A thyroid nodule is a generic term for an occupying lesion in the thyroid gland, either benign or malignant. Most thyroid nodules are usually benign, but some patients have malignant thyroid tumors, which can be graded by further thyroid ultrasound to determine the benignity or malignancy of the thyroid. Some patients may also have abnormal thyroid function, such as hyperthyroidism or hypothyroidism. If the nature of the thyroid nodule is not clear, a puncture biopsy is recommended for a definitive pathological diagnosis. If the thyroid nodule is large, produces pressure symptoms or is malignant, it can be treated by surgery.