Thyroid diseases are one of the most common diseases in the society. Goiter and thyroid nodules appear with increasing frequency with age, and advanced diagnostic methods allow earlier diagnosis of this group of diseases. Thyroid nodules are detected in 4-5 out of every 10 people with ultrasound.
When we look at the treatment methods of thyroid diseases in general, there are 3 basic treatment approaches:
Medication
Radioactive iodine therapy
Surgical treatment-surgery
The treatment step to be discussed here is the radioactive iodine treatment in the field of nuclear medicine, or atomic treatment, as it is known among the people. In patients with toxic goiter and autonomic toxic nodules, radioactive iodine is the most effective, harmless, easiest-to-apply, most cost-effective treatment method. It has many advantages over drug therapy and surgery.
What is radioactive iodine? How does it affect?
At this point, it will be useful to look at how the thyroid produces hormones and to understand how radioactive iodine works.
The thyroid gland is an endocrine gland located anteriorly in the neck and produces the hormones we call thyroid hormones. The thyroid gland uses iodine to produce these hormones. For this reason, in cases where iodine is taken more or less, enlargement and nodules may occur in the thyroid gland.
Radioactive iodine, on the other hand, is the radioactive form of iodine and emits radiation. It is also known as ATOM among the people. Radioiodine given orally as a capsule or liquid is absorbed from the digestive system and collected in the thyroid gland (goiter) cells, just like iodine taken from food, naturally, and the radiation it emits stops the growth and activity of thyroid cells. The function of the overactive thyroid gland returns to normal or unwanted thyroid tissues are destroyed.
In which group of thyroid diseases is radioactive iodine therapy applied?
a) In goiter diseases (toxic goiter) where the thyroid gland is overworked and causes high levels of thyroid gland hormone in the blood;
ü Diffuse toxic goiter (Graves’ Disease).
ü Toxic adenoma: The most effective and only treatment for this disease is radioactive iodine.
ü Toxic multinodular goiter.
ü Non-toxic diffuse goiter.
ü Non-toxic multinodular goiter.
ü Non-toxic uninodular goiter (autonomic nodule, hot nodule).
b) It can be used to reduce the size of the gland in patients with large goiter who are medically prevented from undergoing surgery or who do not accept surgical treatment.
c) In certain types of thyroid cancers;
ü papillary thyroid cancer
ü follicular thyroid cancer
ü Hurthle Cell thyroid cancer
While radioactive iodine treatment is applied by hospitalization for thyroid cancers, hospitalization is not required for the treatment of other thyroid diseases. In this article, radioactive iodine treatment is discussed in diseases other than thyroid cancers.
Who cannot be treated with radioactive iodine?
It is not applied to pregnant or lactating mothers, those who are planning a pregnancy in the next year, as radioactive iodine contains radiation and radiation can be harmful mainly to fast-growing children and babies. In addition, it is not applied in cases where the production of thyroid hormones, called hypothyroidism, decreases, because the effect of radioactive iodine is to reduce the production of thyroid hormone.
It is possible to get pregnant safely 1 year after radioiodine treatment.
What should be considered in patient selection?
There are two basic approaches that are widely accepted in the treatment of thyroid diseases in the world. The first is the American school, the second is the European school. In the American school, radioactive iodine treatment is mostly accepted as the first-line treatment. In the European school, it comes to the fore in the second place in the treatment of patients who cannot benefit from drug therapy.
As it should be in almost all treatment approaches, it is the right thing to discuss and evaluate this treatment model according to the patient’s living conditions and clinical situation, and to decide together with the patient. For example, the approach to a 30-year-old patient with Graves’ Disease who is planning a pregnancy should be different, while the approach to a 55-year-old patient who has the same disease and does not want drug treatment should be different.
In fact, radioactive iodine is the most effective, harmless, easiest-to-apply, comfortable, non-adverse and economical treatment method for patients with toxic goiter and autonomic toxic nodules. When you look at other treatment methods, it is possible that the drugs used in drug therapy weaken the immunity and eliminate the defense against infections, create allergic rashes on the skin or have a toxic effect on the liver. In addition, the patient must be under close and frequent doctor control for drug treatment, and 40-50 out of every 100 patients relapse after drug use is discontinued.
Surgical treatment is likely to cause permanent damage to the nerves going to the vocal cords or to permanently damage the endocrine glands called parathyroid glands. Parathyroid glands are important glands that regulate calcium metabolism and are adjacent to the thyroid glands. Again, before the surgery, the overactive thyroid gland of the person must be brought to a normal working condition, while radioactive iodine treatment can be applied even when the hormone levels are high.
How is radioactive iodine therapy administered? What are the side effects?
Before radioiodine treatment, which is very easy to apply, it is essential that a nuclear medicine specialist evaluates the patient, decides on the treatment dose, suitability, and completes the preliminary preparation. During the preparation stage before the treatment, it is important and necessary for the patient to stop the thyroid drugs used for a certain period of time, and to stay away from foods, drugs and substances containing iodine for a certain period of time. After the evaluation, the patient’s treatment is administered by mouth in capsule or liquid form. The patient does not need to be hospitalized for this treatment. After the treatment, since radiation will be emitted from his body for a certain period of time, he will be asked to limit his association with small children and pregnant women for 7-10 days and to follow some simple rules.
Since radioiodine contains radiation, the possibility of causing cancer or its applicability to a person with another cancer may be questions that come to mind. This treatment method has been used safely all over the world for more than 50 years and it does not cause cancer or affect existing cancer, on the contrary, it is the most effective treatment of thyroid cancers.
A slight decrease in salivation may occur after radioactive iodine treatment, but this is usually a temporary and preventable side effect.
Very rarely 3-5 days after treatment. There may be a period that can last from day 10 to day 10 and can be felt as an increase in the initial complaints. This should not be mistakenly interpreted as a side effect, on the contrary, it is a sign that the drug has reached the thyroid and its effect has begun. However, if the complaints become very disturbing, it is recommended that the patient contact his doctor for evaluation of a special picture called thyroid storm.
When do the effects of radioactive iodine treatment begin to be felt?
Radioactive iodine therapy is not a treatment that shows its effect within a few days. The effect of the treatment begins within an average of 1 month. Blood tests are usually sufficient to evaluate the efficacy of treatment. The goal and measure of success of treatment is not to normalize thyroid hormone levels. After the treatment, the patient’s hypothyroidism indicates that the treatment is effective and is the desired effect. The important thing here is to know; Whichever of the 3 treatment options, namely medication, surgery, radioactive iodine treatment is applied, it is aimed for the patient to enter hypothyroidism with effective treatment. Therefore, it is essential that the person enters hypothyroidism after radioiodine treatment and that the deficient thyroid hormones are supplemented externally. This supplement is necessary for life. The effectiveness of the given radioiodine treatment must be followed up. Very rarely, it may come to the fore that the patient receives a second radioiodine treatment.
