Thyroid cancer therapy

Synonyms in the broadest sense

Therapy thyroid malignoma, papillary thyroid carcinoma, follicular thyroid carcinoma, anablastic thyroid carcinoma, medullary thyroid carcinoma

Therapy

Surgery is the primary form of treatment for malignant thyroid tumors. The entire thyroid gland (= radical thyroidectomy) and the regional lymph nodes, i.e. those adjacent to the thyroid gland, are removed. The operation is followed by radioiodine therapy in the case of iodine-storing tumors.

The aim of this therapy is to remove all the iodine-storing tissue from the body, as any remaining thyroid tissue could lead to the formation of new tumors. Three to four weeks after the operation, a full-body scintigraphy with a low dose of radioactive 131 iodine is performed to detect iodine-storing thyroid remnants and metastases of the carcinoma. This examination is followed by radioiodine therapy: The patient receives a high-dose treatment of 131 Iodine in several doses.

These are repeated until no more iodine-storing tissue can be detected. The radioactive iodine is stored in the cancer cells, but cannot be used to produce thyroid hormones: It destroys the cells due to the radioactive radiation. After the operation and radioiodine therapy, the thyroid hormones must be replaced (=hormone substitution), since the body’s own production is no longer possible.

The stimulation of hormone-producing thyroid cells takes place in a closed control loop: The hormone TRH (=Thyroid Releasing Hormone) is released from the central nervous system and acts on the pituitary gland, which now produces more TSH (=Tyroid Stimulating Hormone) and releases it into the blood. TSH acts on the thyroid gland: the thyroid cells are stimulated to produce hormones, so that T3 and T4 (thyroid hormones) are subsequently released. The low TSH level is achieved by a high therapeutic dosage of the thyroid hormone T4, i.e. a high thyroid hormone concentration T4 in the blood slows down the release of TSH in the sense of negative feedback.

Anaplastic thyroid carcinomas are non-hormone-producing tumors that do not store iodine and are therefore not destroyed by radioiodine therapy. After surgery, external radiation treatment is performed because the undifferentiated tumors are sensitive to radiation. C-cell carcinomas, on the other hand, are resistant to radiation. Radical thyroid surgery is necessary to improve the prognosis for the patient.