Radioisotope treatment of thyroid carcinoma

"Having a multidisciplinary, experienced and coordinated team is important in any pathology. In thyroid cancer, it is more than important, it is vital".


Radioisotope treatment for thyroid carcinoma is a type of metabolic radiotherapy that consists of the therapeutic administration of radioiodine (dose of 100 to 200 mCi).

It is used as a treatment for differentiated thyroid carcinoma, either as a complement to surgery for the destruction of thyroid remains, or as a treatment of choice in the affected area near the resected area and at a distance (metastasis) from the thyroid carcinoma.


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When is radioisotope treatment for thyroid cancer indicated?

Treatment with Iodine-131 is used as a complement to surgery for the destruction of thyroid remains or as a treatment of choice in the near to the resected area and at a distance (metastasis) from the carcinoma.

This treatment is carried out approximately two months after the surgical intervention.

Most frequent indications for this treatment:

Have you been diagnosed with thyroid cancer?

Radioisotope treatment may be necessary

How is treatment with radioisotopes performed?

The administration of radioiodine is usually done orally in a single dose after the patient has been fasting for six to eight hours.

Treatment requires hospitalization of the patient in a room specially adapted to the radiation protection standards established for this purpose.

The patient will remain in this room in isolation (he/she will not be able to leave or receive visitors) until the levels of irradiation decrease (approximately three days). During this time you will receive ongoing nursing and medical care.

Therapeutic administration of radioiodine in differentiated thyroid carcinoma is a radiotherapy treatment and therefore subject to unwanted effects from irradiation.

Due to the long life expectancy of these patients and despite the fact that experience in the treatment of differentiated thyroid carcinoma with radioiodine shows that it is a safe treatment, the possibility of the development of other tumors must be taken into account, especially in those cases treated with high and/or repeated doses.

It should be noted in this section that the administration of radioiodine treatment is contraindicated in pregnant patients because of the risk of radioiodine affecting the development of the child before birth.

Because the body retains radioiodine during the six months following administration, pregnancy should be avoided during this period. Once this time has elapsed, there is no longer any appreciable risk.

The treatment must be indicated by a specialist, once the thyroid gland has been dried out.

As a preliminary preparation, you should suspend hormone replacement treatment (thyroid hormone) at least 4-6 weeks before treatment with radioiodine and follow a diet low in iodine.

Likewise, drugs that interfere with the incorporation of radioiodine (topical iodine tinctures, amiodarone, anxiolytics, antidepressants, etc.) should be avoided as much as possible and under the supervision of your physician.

The recent use of iodized radiological contrasts will force a delay in the administration of the treatment for it to be effective.

In the days following the administration, some discomfort may appear, which is not very important, but it must be known in order to avoid causing concern or anxiety to the patient.

A feeling of gastric heaviness, nausea and rarely vomiting may be noted, so patients are usually treated preventively with antiemetic agents and gastric emptying aids.

It is also possible to notice a sensation of pressure on both sides of the jaw due to a discrete inflammation of the salivary glands along with dry mouth and loss of taste. This effect disappears in most cases by facilitating salivary secretion.

Occasionally, discreet ciscitis occurs as a result of the elimination of radioiodine in the urine. To avoid this, it is advisable to increase fluid intake.

Other possible side effects, such as a feeling of tension in the neck, may occur depending on the amount of thyroid remains after the operation. However, if they appear they are easily treatable with anti-inflammatory drugs.

Where do we do it?


The Thyroid Pathology Area
of the Clínica Universidad de Navarra

The Thyroid Pathology Area is made up of a multidisciplinary team of specialists who work together to offer patients with thyroid problems an accurate diagnosis.

After the diagnosis, the patient is indicated the most appropriate treatment for his or her case and a continuous follow-up is carried out to achieve the desired objectives.

The Clinic is a pioneer in the implementation of medical techniques in Spain and worldwide, and is an international reference in highly specialized procedures.

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Why at the Clinica?

  • Prestigious professionals who are a national reference.
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