La thyroïde est un organe qui se situe au milieu et à l'avant du cou. Elle est positionnée devant la trachée et à proximité des nerfs récurrents qui commandent les cordes vocales et le larynx. Lorsqu'un cancer apparaît, les cellules cancéreuses sont d'abord peu nombreuses et limitées à la thyroïde. Avec le temps, la tumeur peut grossir et s'étendre au-delà de la thyroïde. Parfois, plusieurs tumeurs se développent en même temps sur la thyroïde. Au moment du diagnostic, les médecins étudient précisément l'étendue du cancer afin de vous proposer le ou les traitements les mieux adaptés.


The thyroid requires a small quantity of iodine to function correctly; a high level of iodine can therefore prevent the excessive release of hormones. Treatment with iodine is therefore a short-term option to control hyperthyroidism, but in some cases surgery is required. Following surgery, the patient is treated with radioactive iodine.


Following surgery on the thyroid, treatment with radioactive iodine is advised for two purposes:

> To destroy any remaining thyroid cells after surgery, thereby facilitating later monitoring of the patient’s condition

> To destroy any remaining thyroid tumour cells, thereby reducing the risk of reoccurrence

Radioactive iodine is administered as a single capsule taken upon admission to hospital. It is administered by a doctor specialising in nuclear medicine.

Once the iodine capsule has been absorbed, the radioactive iodine enters the thyroid cells, where it acts as a therapeutic agent. The iodine emits rays that can be detected by a gamma camera.

Thyroid cells that have absorbed enough radioactive iodine are visible. This makes it possible to see whether any thyroid cells are present in other parts of the body.


Once the iodine capsule has been absorbed, all liquids in your body become radioactive.Radioactive iodine is expelled primarily in urine, but also in faeces, saliva, sweat and menstrual blood.

Although the level of radioactivity in the body rapidly decreases over time, it remains significant for the first few days. You must therefore remain in hospital in a private “protected” room in the brachytherapy department [curiethérapie], on the ground floor of the hospital admissions building (door A) of the Eugène Marquis Centre.

The room has a bathroom, a television, a telephone and other usual conveniences. You are allowed to open the windows if you want.

Iodine treatment does not require any specific medical devices, with the exception of the toilet bowl which is used to collect urine separately.

The staff (nurses and healthcare assistants) will be at your service throughout your stay and can enter your room, but only when necessary.


To encourage iodine expulsion, during the first 48 hours it is recommended that you:

  • drink plenty of liquids (up to two litres a day) to help iodine expulsion via the kidneys.
  • take a sip of lemon or orange juice every half an hour to encourage the flow of saliva and prevent iodine accumulation in the salivary glands. Acidic sweets are also provided.

As some iodine is expelled in the faeces, it is best to make sure that food moves through the digestive system at a reasonable pace. If you are constipated, please tell your nurse.


Your time in hospital

Please shower and wash your hair at home the morning before your procedure. You will only be able to take a shower again on the day you leave the hospital. If you want to wash, you will have to do it in the sink.

To protect others from radiation, you will not be allowed to leave your room. You can use the telephone whenever you want.

Visitors are not allowed during your entire hospital stay.

Medical and paramedical staff will spend as little time as possible in your room in line with safety guidance on radiation protection.

As a safety precaution, the radioactivity level in your body will be measured before you are discharged.


Returning home

In the week following your time in hospital, a scintigraph will be performed in the nuclear medicine department to re-examine the distribution of iodine throughout your body.

 Precautions to take upon your return home

For four days after you return home (or longer if recommended by your doctor), it is advised that you take the following protective measures:

  • Avoid spending too much time in physical proximity to family and friends (no cinema trips, no car journeys longer than an hour, no long-distance public transport). This is particularly important around young children (under 5) and pregnant women. It is very important that you do not hold any young children in your arms. These precautions should be taken until your scintigraph has been carried out and your doctor is happy for you to return to normal.
  • Take a shower (including your hair) before dressing in your normal clothes.
  • Immediately wash the clothes used during your stay, separately from other clothes (but otherwise as you would normally wash them).
  • If possible, you should sleep in a separate bedroom for a few days.

Get the support you need

You can meet with a psychologist and/or social worker at the Eugène Marquis Centre. Talk to your doctor or a technician in the department, who will refer you to the Centre’s support care team.

Our team

BARGE Marie-Luce

Dr BARGE Marie-Luce Nuclear medicine


Dr DEVILLERS Anne Head of Nuclear Medicine Department