Radioactive iodine treatment

Radioactive iodine therapy is performed for treating local and distant metastases.


The radioactive substance and iodine are combined in the laboratory environment to obtain a substance.  It is provided to the patient in form of capsule.  Thyroid cells, which may be left behind after surgery and metastatic lymph nodes absorb this radioactive substance when they want to keep the iodine.  This substance secretes radiation and kills the cancerous cells.


The level of TSH should be above 30 for an effective radioactive iodine treatment. This means that the thyroid tissue should not be left behind.  If too much thyroid tissue is left behind, the radioactive substance accumulates in this tissue and cannot reach the targeted metastatic tissues.


Radioactive iodine therapy also affects lung metastases of papillary cancers and extends the patient's life span.


Whole-body scintigraphy is performed after radioactive iodine therapy.  Metastases that could not be detected previously can be detected by the scintigraphy.


Radioactive iodine therapy is repeated if necessary.


When a patient who uses thyroid hormone is receiving radioactive iodine therapy, the drug is discontinued and the level of TSH is expected to elevate above 30.  It is recommended to avoid iodized materials and food.  These recommendations are explained to the patients by the Nuclear Medicine Specialists.


Radioactive iodine therapy is administered in cases of papillary thyroid cancer tumor that measured larger than 1 cm.  Usually a dose of 100 mC is administered.


Radioactive iodine therapy is performed in cases of cancer tumor that measured less than 1 cm.


 Radioactive iodine therapy is used in follicular cancers as well.


Radioactive iodine therapy is not used in medullary and anaplastic thyroid cancers.