Whether a thyroid nodule of 14 mm is serious or not needs to be considered in conjunction with the location and nature of the nodule and whether there are any changes in thyroid function, and cannot be judged by the size of the nodule alone. If the nodule has pressure symptoms, such as breathing difficulties, it is usually more serious. It is recommended to seek medical advice and treatment under the guidance of a doctor. The cause and pathogenesis of thyroid nodules remain unknown. Benign thyroid nodules include multinodular goiter, Hashimoto’s thyroiditis, cysts, and follicular adenomas. The vast majority of malignant nodules are thyroid carcinomas, and a few are primary thyroid lymphomas or metastatic thyroid carcinomas (breast cancer, renal cancer, etc.). Thyroid nodule 14 mm is usually more serious if diagnosed as papillary thyroid cancer, follicular cell carcinoma, etc. Surgery can be considered under the supervision of a doctor. If the symptoms of Thyroid Nodule 14mm persist without relief, you need to seek medical treatment.