The minimum life expectancy of medullary thyroid cancer depends on the patient’s specific condition, treatment and whether there is distant metastasis, which should be analyzed on a case-by-case basis. In clinical practice, medullary thyroid cancer has a high degree of malignancy. If the patient does not have distant metastasis and there are no symptoms of compression, the treatment should try to remove the thyroid cancer tissue and perform lymph node dissection at the same time. In this case, patients usually live at least 10 years, but the exact time varies from person to person. However, if the patient has distant metastasis and compression symptoms, such as enlargement of both thyroid glands at the same time, the patient will easily invade the laryngeal nerve or metastasize to the lymph nodes in the neck, resulting in hoarseness, which is usually life-threatening within six months. Therefore, patients with medullary thyroid cancer should have regular review after surgery, quit smoking and drinking, maintain a happy mood, increase physical exercise appropriately, and undergo corresponding radiotherapy and chemotherapy when necessary.