Radioiodine Therapy ( abbreviated RIT ) or Radioiodine Therapy ( RJT ) is a special form of radiation used exclusively for various benign and malignant diseases of the thyroid gland.
The patient is usually given in tablet form a special type of iodine, which emits radioactive radiation administered. The body treats it like normal iodine and absorbs it almost exclusively in the thyroid gland. Radiation selectively destroys thyroid tissue while sparing other organs and tissues.
The therapy must take place at a special nuclear medicine ward and is associated with a hospital stay of at least 2 days.
Radioiodine therapy is a special form of treatment used exclusively for diseases of the thyroid gland.
The indications range from benign illnesses to certain forms of thyroid cancer. The method of choice is radioiodine therapy in so-called thyroid autonomy.
In this disease is thyroid tissue, which has escaped the control mechanisms of the body and produces unrestrained thyroid hormones. Radioiodine therapy can specifically destroy the diseased tissue.
It also comes in the autoimmune disease Graves disease to increased thyroid hormone production. In this condition, radioiodine therapy can also be used.
In most cases, the target must be destruction of the entire thyroid tissue in order to achieve healing. Furthermore, the radioiodine therapy is used in various forms of thyroid cancer.
However, this therapy is only possible if the cancer cells, like healthy thyroid cells, also absorb iodine and have not lost this property through degeneration. The alternative to radioiodine therapy is often surgery. In some cases, such as thyroid cancer, both procedures are often combined.
After surgical removal of the thyroid, radioiodine therapy is then performed to destroy any remaining thyroid tissue. In many cases and with timely therapy, thyroid cancer can be cured in this way.
Graves' disease is a disease that leads, inter alia, to hyperthyroidism.
Responsible for this are so-called antibodies ( proteins released by immune cells ), which the body produces and which stimulate the thyroid gland to a pathologically increased hormone production ( autoimmune disease of the thyroid gland).
Those who are ill are usually treated first with drugs that inhibit the excessive hormone production of the thyroid ( for example, carbimazole ). If treatment with these so-called antithyroid drugs does not lead to healing, radioiodine therapy is often recommended in addition to surgery.
This specifically destroys the thyroid tissue. As a result, as a rule, no or too few thyroid hormones are formed, they usually have to be replaced for life with tablet intake.
In advance of radioiodine therapy, no special preparation is often required.
In certain indications, however, a 4-week intake of thyroid hormone preparations must be carried out in advance.
Through this so-called suppression treatment, the body is pretended too high a hormone production and thereby the thyroid hormone ( TSH ) is lowered. This in turn means that the iodine uptake of healthy thyroid tissue is shut down. Thyroid cells with abnormally increased hormone production are no longer under the influence of TSH.
In radioactive iodine therapy, only the autonomous thyroid gland with its unrestrained function absorbs the radioactive iodine. Healthy cells are spared as much as possible at a reasonable dose from radiation.
Radioiodine therapy in Germany may only take place under inpatient conditions. This means that you will be hospitalized for a few days on a special nuclear medicine ward. These stations are equipped with special radiation protection devices, such as sewers or lead-reinforced doors. Otherwise, these are normal patient rooms and not bunkers or lead chambers, as is sometimes claimed.
The actual therapy begins by administering to the patient radioactive iodine as an active ingredient, usually in the form of a tablet for swallowing. After that, the patient can retire to his room.
The body absorbs the radioactive iodine via the intestine and then passes into the blood.
About the circulation, it is initially distributed in the body. The radioactive iodine is stored almost exclusively by the thyroid gland.
Excess iodine is excreted by the kidneys through the urine, leaving the human organism.
In order not to endanger fellow human beings, especially pregnant women and children, the patients must not leave the ward nor receive a visit until the radiation subsides.
This is measured daily and is often after 2 days, but rarely after a maximum of 12 days, to the extent that the patient can be discharged.
After the therapy a blood control of the thyroid values must take place at regular intervals. After about 6 months, a scintigraphy, that is, a measurement of thyroid metabolism, is made to evaluate whether radioiodine therapy has been successful.
Radioiodine therapy has few side effects. Since the radiation used starts from radioactive iodine, which is absorbed mainly by the thyroid gland, the rest of the body is spared.
After the treatment, in about one of 20 therapy cycles, a temporarily painful inflammatory reaction of the thyroid gland may occur ( radiation thyrotropitis ). The doctor then prescribes a so-called ice tie and pain medication, which alleviates the discomfort.
In rare cases, the inflammatory response is cushioned by a short-term treatment with cortisone.
Since radiation is deliberately carried out from the inside during radioiodine therapy, typical side effects of "normal" external radiation such as hair loss, nausea or diarrhea do not occur.
A side effect, which must be accepted in part, is that the body produces by the destruction of the thyroid tissue, no or too few thyroid hormones.
In order to prevent hypofunction, they must be replaced by a life-long intake of thyroid hormone preparations ( for example thyroxine ).
In Graves' disease or malignant disease, this is a concomitant consequence of successful radioiodine therapy, as all thyroid tissue must be destroyed to achieve healing. In thyroid autonomy, however, can usually get enough healthy thyroid areas for a sufficient function.
Weight gain is not a direct consequence of radioiodine therapy. Targeted destruction of the thyroid tissue can lead to hypothyroidism after therapy.
In the treatment of Graves' disease and other malignant diseases, this is usually unavoidable, while it occurs in thyroid autonomy as a side effect.
In any case, hyperthyroidism should be treated by the administration of thyroid hormone preparations, such as thyroxine in tablet form.
If this is not done, in addition to many other episodes of under-functioning, weight gain can actually occur.
However, as routine monitoring of thyroid function is routinely performed after radioiodine therapy, hypothyroidism is usually recognized in time, and weight gain can be counteracted by treatment with, for example, thyroxine .
However, if weight gain occurs, it is likely to have other causes. Mostly because of a high calorie diet and inadequate physical activity.
Side effects in the eyes are not to be feared by a radioiodine therapy. Radiation, which has a targeted effect on the thyroid gland, spares other organs, such as the eyes. Changes in the eyes or impaired vision must have a different cause and should be examined by an ophthalmologist.
Hair loss by radioiodine therapy is not expected. Although it is also a form of radiation, but this is done from the inside and has a targeted effect on the thyroid tissue.
Radiation from the outside in the head area, like a brain tumor, can lead to hair loss.
Although radiation is released during radioiodine therapy, side effects on the bone marrow are not to be feared.
This is because the radioactive iodine acts specifically on the thyroid tissue. The dreaded in other forms of radiation side effects are not to be feared in the radioiodine therapy.
However, drugs that are often used to reduce thyroid function prior to radioactive iodine therapy can rarely lead to changes in the blood count ( for example, by carbimazole ).
But this is not a side effect on the bone marrow, but a kind of allergic reaction in which defense cells of the blood are destroyed.
In the long run, any radioactive radiation to which the body is exposed increases the risk of malignant diseases of the bone marrow ( blood cancer or leukemia ).
In addition to natural radiation in our environment and X-ray examinations, this also includes radioiodine therapy. However, it is not a direct trigger of such a serious illness.
Even if the radioactive iodine administered during radioiodine therapy is absorbed almost exclusively by the thyroid gland, a small proportion also enters the salivary glands.
As a result, less saliva is formed. However, as this is important, among other things, to dissolve flavors, some people complain about a disturbed sense of taste a few days after the therapy.
This side effect, however, usually goes back by itself and the taste comes back gradually.
Prevention can be chewed on the disturbed sensation by chewing gum and sucking sour candy, to stimulate the salivation. It is also important to drink enough.
Side effects on the skin are not expected in radioactive iodine therapy. While in other forms of radiation, the radioactivity acts on the outside of the body and thus usually also the skin is affected, this danger does not exist in the irradiation from the inside by the radioactive iodine.
Only on the mucous membrane of the stomach can a brief irritation by the capsule with the radioactive iodine come, which is noticeable by nausea and full feeling.
The main advantage of radioiodine therapy over surgery is that it specifically destroys only thyroid tissue while sparing other organs and tissues.
There is no need to cut, you do not need anesthesia and there is no scar left. Radioiodine therapy has few side effects and the risks associated with surgery are avoided.
In addition to the general anesthetic and surgical risks, this particularly includes a possible impairment of the voice if the nerve supplying the larynx is injured. This runs in close proximity to the thyroid gland.
The risk of a wound healing disorder is bypassed.
In addition, there is always the danger that the parathyroid glands necessary for the calcium metabolism will be removed during an operation. Radioiodine therapy, on the other hand, does not affect the function of the parathyroid glands.
During surgery, it can happen that the thyroid tissue can not be completely removed or remains are overlooked. Radioiodine therapy can more effectively achieve complete removal if a sufficient dose of radiation is selected.
Even if metastases have already spread to other organs in a malignant thyroid disorder, in some cases radioactive iodine therapy can help reduce it, or even destroy it in the best case, and thus achieve healing.
The main disadvantage of radioiodine therapy over surgery is that it can not be used on pregnant and nursing women.
In addition, the radioiodine therapy must be carried out on a special nuclear medicine ward, which should not be left until the radiation subsides. The patient may not even receive a visit from relatives during this time. Some patients find the stay very boring and lonely.
Furthermore, the radioiodine therapy can be unsuccessful if the administered radiation was insufficient and must then be repeated if necessary. The more radioactive radiation a person is exposed to, the higher the danger of eventually suffering a malignant disease. Therefore, this risk is somewhat increased by the radioiodine therapy as opposed to surgery.
How long a radioiodine therapy lasts can vary widely and can not be predicted in advance.
It depends on the size of the irradiated thyroid volume and the radioactivity administered. Discharge from the ward may only take place when the radiation emanating from the patient has fallen below a threshold and no longer poses any danger to the people around them.
The radiation is therefore regularly monitored by measurements at the same distance. Some patients may be allowed to go home after just two days.
On average, the stay is five days. In exceptional cases, however, the radiation may also slow down only very slowly so that the patient may only leave the ward after up to twelve days.
As a rule, after discharge from the nuclear medicine station after radioactive iodine therapy no more work incapacity is given.
In certain exceptional cases, however, certain precautionary measures should be taken for safety. Above all, in the first few days this means avoiding close contact with fellow human beings and keeping as much distance as possible.
When working with children (for example kindergarten teachers or teachers) or if there is a prolonged contact (over two hours) at the workplace with the same people, the attending physician may certify a longer duration of illness.