Patient: Description (onset, main symptoms, hospital visited, etc.): In 2003, the left thyroid gland was removed and some of the lymph was cleared, and in March 2011, two 2.1-2.0 cm lymphomas were detected by ultrasound. On July 22, another 1.4 – 0.7 cm enlarged lymphoma was found on the follow-up examination. I took 2.5 tablets of Eugenol orally on an empty stomach every day, and was treated with iodine 131 at the Provincial People’s Hospital on March 28. Is this appropriate? Some people say there is no need to do iodine 131 treatment. Chen Wanjun: Since iodine therapy is an important treatment for the thyroid gland, many thyroid cancer patients ask for iodine therapy. In fact, the most important thing is that we have to figure out under what circumstances do thyroid cancer patients need iodine therapy? Or what kind of thyroid cancer patients need iodine therapy most? Otherwise, there will be over-treatment, which is harmful but not beneficial. 1.Pathologically, only differentiated thyroid cancer can do iodine therapy, which means papillary carcinoma and follicular carcinoma absorb iodine and iodine therapy may be effective; medullary carcinoma and undifferentiated carcinoma do not absorb iodine and iodine therapy is ineffective. Iodine therapy is a kind of palliative treatment measure, which is most suitable for patients with differentiated thyroid cancer with lung metastasis and bone metastasis. Iodine therapy is not needed for thyroid cancer with lymph node metastasis in the neck as long as it can be removed and excised cleanly, and iodine therapy can be chosen after surgery if the tumor invades important structures such as the aorta of the neck and cannot be completely removed. 3. Because partial or major thyroid gland resection and neck clearance are done for thyroid cancer, iodine therapy is ineffective and harmful when there is no distant metastasis. This is because all the iodine is absorbed by the remaining thyroid tissue, resulting in a lesion that does not absorb iodine. In this way, not only is money spent, but most importantly, the patient’s thyroid function is completely destroyed and he or she needs to take thyroxine tablets for life. 4. Since there are remaining thyroid tissues that strongly absorb iodine, resulting in residual lesions and distant metastatic lesions that do not absorb iodine, any patient who needs iodine therapy needs to have a total thyroidectomy, otherwise it is ineffective. 5.Since iodine therapy is a palliative treatment measure, any lesions that can be removed from thyroid cancer should be surgically removed to achieve good therapeutic effect.