Guidelines on TSH suppressive therapy: 1. What kind of thyroid cancer requires TSH suppressive therapy? TSH suppressive therapy can reduce the chance of thyroid cancer recurrence after surgery to some extent. Common thyroid cancers include papillary carcinoma, follicular adenocarcinoma, eosinophilic carcinoma, medullary carcinoma, undifferentiated carcinoma, and non-Hodgkin’s lymphoma. Although they are all malignant tumors that occur in the thyroid gland, they originate from different tissue types. For example, papillary carcinoma, follicular adenocarcinoma, and eosinophilic cell carcinoma originate from the follicular epithelium of the thyroid gland and are therefore responsive to TSH and thus can be treated with TSH suppression. Medullary carcinoma and non-Hodgkin’s lymphoma originate from parafollicular cells and lymphocytes, respectively, and are not of thyroid follicular epithelial origin, so their growth is not affected by TSH, and therefore TSH suppressive therapy is also ineffective. 2. How is TSH suppressive therapy administered? TSH suppression therapy can be achieved by oral administration of levothyroxine. In normal human body, TSH can promote the secretion of thyroid hormones, while thyroid hormones above the normal level can inhibit the secretion of TSH, which makes TSH and thyroid hormones control each other through negative feedback regulation and finally reach a balanced state. Based on the above principle, as long as the patient takes more exogenous thyroid hormone than the body needs, the TSH secretion by the body itself can be suppressed at a lower level, thus serving the purpose of TSH suppression therapy. 3.How to determine the dosage of levothyroxine? The response of different individuals to exogenous thyroid hormone is different, so clinically we determine the dose of oral thyroid hormone by testing the concentration of TSH. The level of TSH suppression to be achieved varies in people with different postoperative propensity for recurrence. A. Patients with known residual lesions or those at high risk of postoperative recurrence need to control blood TSH levels to less than 0.1 mU/L. B, Patients with low postoperative risk of recurrence can control blood TSH levels at low normal values. C. Patients with low postoperative risk of recurrence need to control blood TSH levels at 0.1 C 0.5 mU/L if positive thyroglobulin is found during follow-up but no evidence of recurrence is detected on imaging. D If no signs of recurrence are found in postoperative patients with nail cancer after years of follow-up, TSH can be considered to be adjusted to within the normal range. 4.What things should be noted during suppression therapy? A.Cardiovascular complications such as tachycardia, hypertension and even heart failure can occur in middle-aged and elderly people taking thyroid hormone. A decision should be made whether to continue TSH suppression therapy after balancing the pros and cons. B. Some patients, especially postmenopausal women, are prone to osteoporosis and other manifestations, so oral calcium and vitamin D3 can be considered. C. Excessive thyroid hormone levels may also cause some other adverse reactions, so it is recommended to follow the doctor’s instructions and not to change the dose of medication without authorization. If you experience discomfort, you should seek medical attention promptly to clarify whether it is due to drug overdose and take appropriate treatment measures.