What is iodine therapy?
Radioiodine therapy is a nuclear medicine treatment. Doctors use it to treat an overactive thyroid, a condition called hyperthyroidism. They also may use it to treat thyroid cancer.
The term “radioactive” or “Chemotherapy” may sound frightening, but it is a safe, generally well-tolerated, and reliable treatment that targets thyroid cells so there is little exposure to the rest of your body’s cells
What measures should be taken for iodine therapy?
Your doctor will instruct you on how to prepare, how to take any necessary radiation safety precautions, and when to stop taking anti-thyroid medications. Tell your doctor if there’s a possibility you are pregnant or if you are breastfeeding. Discuss any recent illnesses, medical conditions, allergies, and medications you’re taking. This procedure requires little to no special preparation. However, you should not eat or drink anything after midnight on the day of treatment.
How does radioactive iodine treat hyperthyroidism?
Your thyroid, a butterfly-shaped gland located in the lower front of your neck, produces hormones that regulate your body’s metabolism and other functions
The thyroid gland needs iodine to make these hormones. That iodine comes from the food you eat. No other organs use or absorb much iodine from your blood. Excess iodine in your body is excreted in the urine Therefore the thyroid is the most efficient organ at concentrating iodine. RAI treats hyperthyroidism by damaging or destroying thyroid cells through radiation.
RAI is taken in an oral capsule form. You don’t need to be hospitalized unless the dose is very high, which is rarely needed. You will be prompted to drink lots of water after taking the pill to flush the remaining radioactive iodine out of your system.
Most patients need only one dose before their hyperthyroidism is resolved, which may take a few weeks to several months. If your symptoms are still there after six months, you may have to receive a second dose.
What is the effect of iodine therapy in the treatment of thyroid cancer?
The radiation will kill the thyroid gland and, if the treatment is for thyroid cancer, any thyroid cancer cells that might have traveled and settled in other organs.
Most other cells are not interested in taking up iodine, so the treatment is very safe. Very high doses can sometimes decrease the production of saliva (spit) or injure the colon or bone marrow.
When thyroid iodine therapy done?
Radioactive iodine therapy helps people live longer if they have papillary or follicular thyroid cancer (differentiated thyroid cancer) that has spread to the neck or other body parts, and it is now standard practice in such cases.
The therapy is usually given after removal of the thyroid gland to destroy any remaining thyroid tissue. A “tracer” dose of radioactive iodine can also be used to track remaining thyroid tissue and/or cancer that could have spread to other parts of the body.
RAI can be given as early as 4-5 weeks following total thyroidectomy but can be delayed for months or even years following surgery. The papillary thyroid cancer must have the symporter for iodine and take up iodine to be effective.
References
https://www.radiologyinfo.org/en/info/radioiodine
https://my.clevelandclinic.org/health/treatments/16477-radioiodine-radioactive-iodine-therapy
https://medlineplus.gov/ency/article/007702.htm
https://www.thyroidcancer.com/thyroid-cancer/papillary/radioactive-iodine-treatment
https://www.cancer.org/cancer/thyroid-cancer/treating/radioactive-iodine.html
