Molecular Radiotherapy Series No. 6 - Information for parents of children and young people having radioactive iodine (131I) treatment

We want to involve you and your child in all the decisions about their care and treatment. If you decide to go ahead with treatment, by law, we must ask for your consent and will ask you to sign a consent form. This confirms that you agree to your child having the procedure and understand what it involves.

Staff will explain all of the risks, benefits and possible alternatives before they ask you to sign a consent form. If you are unsure about any aspect of your child’s proposed treatment, please do not hesitate to speak to speak to the team looking after your child.

Radioactive iodine (131 I) is a form of radiotherapy treatment called molecular radiotherapy (MRT). It has been used to treat thyroid cancer for many years. It is a targeted method of destroying any remaining normal thyroid tissue or thyroid cancer cells that may remain following your child’s total thyroidectomy surgery.

The thyroid gland and related cells need iodine in order to work. They take up any iodine in the body. This then releases radiation in the parts of the body where it has been absorbed, providing an easy way to target the radiation to areas in the body where it is needed. Radioactive iodine ( 131 I) treatment together with surgery will maximise the chances of eradicating your child’s cancer.

The need for treatment depends on the risk that your child’s cancer might progress after surgery. It is not needed for very tiny cancers which have been removed.

It is certainly needed in high-risk patients where the disease has spread. Some patients with lower risk may choose not to have this treatment. However, this is something that you should discuss with the clinical oncologist treating you before making a decision.

At the first visit you and your child will meet the consultant clinical oncologist who will talk to you about the plan for their treatment and explain what to expect. You will also meet the other members of the medical team who will be treating your child. You and your child will have a chance to ask any questions you may have at this appointment.

We will take you to the paediatric oncology ward (T11N) to meet some of the nurses who will be looking after your child. We will show you the protected rooms in which your child will be staying for the duration of their treatment. You will also meet the molecular radiotherapy team who will coordinate your child’s care and treatment.

Visiting the ward and treatment rooms, and meeting the staff involved in your child’s care, will give you a better understanding of what to expect and ensure your child is comfortable and familiar with what is happening (Fig 1.).

We can contact the play specialists in advance to ensure toys and activities your child enjoys are available in the room for the duration of your child’s stay.

For a good uptake of radioactive iodine (131I), your child’s blood levels of thyroid stimulating hormone (TSH) need to be high. To stimulate their levels of TSH, they will need to stop certain medications or have injections to ensure their treatment is effective. The doctor will advise which method is best for them.

Patients are given injections of rhTSH (thyrotropin alfa), also known by the trade name of Thyrogen. These allow your child to carry on taking their thyroid medication throughout treatment and are given as outpatient appointments before treatment.

However, not all patients are suitable, or able to have Thyrogen injections. If this is applicable to your child, they will need to stop your Levothyroxine Sodium (T4) four weeks before admission or your Liothyronine (T3) ten days before admission. Your child may feel tired or weak when not taking the tablets. This is normal and the symptoms will disappear once they start taking the tablets again, which is normally on discharge from hospital. 

Two weeks before admission your child should avoid iodine-rich foods. Eating these foods may reduce the effectiveness of treatment. We advise that they:

• Do not eat fish, kelp and all seafood.
• Do not take vitamin supplements which contain iodine or cod liver oil.
• Do not take cough medicine, iodised table salt or sea salt.
• Do not eat foods artificially coloured pink or red such as canned and glacé cherries, canned strawberries, spam and salami. These contain the colouring material E127 which is rich in iodine.
• Certain CT scans use iodine-based contrast – if you are having a CT prior to treatment please inform your doctor or the MRT radiographer booking your treatment. If you have had a recent CT scan with iodine-based contrast your treatment will be delayed for three months.

Please continue taking any other medications that they have been prescribed, and bring a supply with you on admission and show them to the doctor who examines your child.

Your child should not have radioactive iodine (131I) treatment if they are pregnant or breastfeeding. You must tell the staff if there is any chance of them being pregnant.

All individuals with internal reproductive organs (a uterus) over the age of 12 will have a pregnancy test before treatment starts. Your child should not become pregnant for at least six months after treatment. Individuals with external reproductive organs (testes) should not conceive a child for at least four months after treatment.

The MRT radiographers will discuss any issues around sex, contraception and intimacy with your child if it is appropriate.

Your child will be admitted to the paediatric oncology ward on the 11th floor of the main UCH building (T11N) on the day of their treatment and allocated a protected room with en-suite shower and toilet (Fig. 2).

There is available space outside the room, to allow you to stay in hospital with your child for the duration of his/her treatment. (Fig.3, Fig.4).

Before administration of the radioactive iodine, your child will have a blood test to measure their thyroid-stimulating hormone levels and be given anti-sickness drugs to reduce the risk of them feeling sick or being sick after treatment.

The treatment is routinely given as a small capsule and your child will be given some water, juice or yoghurt to help you swallow it. Please let us know at the earliest opportunity if they cannot swallow capsules, as we would give the treatment in liquid form instead.

Your child will need to be an in-patient for three to five days. However, their stay may be longer, dependent on your family and home circumstances. During their admission your child will have a whole-body scan in the nuclear medicine department. The scan produces a map to see where the iodine (131I) has been absorbed in their body. A porter will collect you and your child and take you both directly to the nuclear medicine department for the scan. Your child can watch something on an iPad or tablet, or listen to music during their scan. The play specialist will be available to support your child during the scans.

The radioactive iodine (131 I) treatment will enter your child’s bloodstream and iodine 131I will be absorbed by any remaining thyroid tissue or thyroid cancer cells. Most of the remaining iodine (131 I) will be excreted through their urine over the following days. It can also be excreted in other bodily substances such as saliva, vomit, faeces, sweat and oils secreted by their skin.

The radiation from iodine (131 I) is treating your child’s cancer but it could be a risk to other people. Your child will therefore stay in a protected room to reduce any radiation exposure to other people.

Strict regulations state that patients receiving radioactive drugs must stay in hospital until most of it has been excreted. Other rules are:

• Your child must not leave the room.
• Your child must only use the shower and toilet in the en-suite.
• The en-suite shower and toilet cannot be used by anyone else.
• Your child must only wash and dry their hands using the paper towels in the room and throw of them in the yellow bin bags.
• One of the two doors to the en-suite must always be closed (Fig. 5)
• All medical and nursing staff and visitors entering the room must wear protective shoe covers, aprons and gloves.
• Anyone entering the room must wear a radiation monitor and record their measurements.
• If your child feels sick, please tell the nursing staff immediately. Your child can use the toilet in the en-suite to be sick in. The nurses can also provide a disposable bowl.
• If your child wears nappies or pull-ups, please discuss with the MRT radiographers, who will advise on their disposal during admission.
• Please encourage all children or young people to sit, rather than stand, whilst urinating, to minimise the risk of contamination in the bathroom.
• Please double flush the toilet.

Your child will stay in the protected room most of the time during treatment. Exceptions include going to the nuclear medicine department for scans or in a medical emergency.

Your child should only bring items they will not need to take home immediately.

This is because any personal possessions brought in will become contaminated with radiation. You may need to leave some things behind if they carry traces of radioactivity. The radiotherapy physics team will monitor the radiation levels of your child’s belongings and let you know if there are any items they need to store.

These items may need to be kept for up to three months.

If you or your child would like them back, please let us know and we can contact you when they are ready to be collected We will ask your child what their interests are, and the hospital’s play specialists will try to provide activities and toys which your child particularly enjoys. This means that they will not need to bring items from home.

Your child will be able to play video games, watch TV and/or DVDs or play with the toys which are all provided in the room (Fig.6).

Old and comfortable clothes are best for your child to wear while they are admitted to hospital. The strength of the Wi-Fi signal in the room can sometimes vary. We are working to improve this. It is best not to rely on the Wi-Fi. If you are uncertain on what things you can bring in due to the risk of radiation contamination, please ask the MRT radiographers.

We recommend that one person stays throughout your child’s stay in hospital to help with their care. You may be asked to take some radiation measurements for your child during the course of the week. This will help the team to accurately calculate the dose needed for future treatments. The nuclear medicine team will give you more information about this when your child is on the ward.

There are legal limits to the amount of radiation people can have. It is important we keep your personal radiation exposure as low as possible, while allowing you to spend as much time as possible with your child. We will show you ways in which you can minimise your personal radiation exposure. Following training, you will be asked to sign a consent form to be a comforter and carer. By signing this consent form you agree to receive a higher radiation dose than normally permitted, and can therefore spend as much time with your child as they require.

To minimise and record your personal radiation exposure you must:

• Wear protective shoe covers, aprons and gloves in the room at all times.
• Wear a radiation monitor.
• Minimise the time you spend with your child and maximise the distance between you.
• Stay behind the mobile lead shields placed round your child’s bed as much as possible.

Whilst your child is sleeping, playing or resting, we will advise you to stay in the parent cubicle.

As a comforter and carer, you will not be radioactive and so you may wish to swap with other family members and return home to visit other children. You may also wish to bring with you your mobile phone, tablet, laptop or Kindle during your child’s stay, however they will always need to remain in the parent area. There is guest Wi-Fi available for visitors of UCLH.

Please tell us if your child has any accidents with bodily fluids while in hospital. It may be harmful to yourself and others if you fail to tell us.

Adult visitors, other than parents, who are not pregnant, are allowed to visit twenty-four hours after treatment. Adults may visit for up to one hour and sit outside the protected room behind a lead screen.

All visitors must report to the nurse’s station on arrival. Visitors under 18 and any pregnant or breastfeeding family members cannot visit under any circumstances.

T11N is a paediatric oncology ward. The protected rooms are reserved for children and adolescents of all ages admitted for radioactive treatments. Your child will have a nurse who will be responsible for their care throughout their stay on the ward.

Meals will be brought to your child in their room three times a day. Meals will be served on paper plates with plastic cutlery for easy disposal. If your child does not get a meal, please let a nurse know. Please also let us know if your child has any special dietary needs.

A microwave and kettle are also available in the parents’ room on T11N. Tea, coffee, juices, cereals and some other food items will also be available. Food from outside the hospital is permitted and a wide range of shops and food outlets can be found a short distance from UCH.

Accommodation may also be booked for you and other family members to stay during your child’s treatment. Please speak to your MRT radiographers for further information.

During your child’s stay on the ward, you may gather lots of different waste in the room. We would like you to separate the waste into different bins to ensure that we can reduce the volume of radioactive waste. The categories of waste are:

Non-clinical waste that has been in the mouth

Examples include:

• Disposable cutlery
• Empty cans/cups
• Food contaminated waste

The items that have been in your child’s mouth and have had saliva on them are more contaminated than waste that has not been in his/her mouth.

Non-clinical waste that has not been in the mouth

Examples include:

• Sweet and crisp wrappers
• Fruit peels
• Newspapers/ magazines
• Teabags

Clinical waste

Examples include:

• Waste with bodily fluids
• Dressing and plasters
• Gloves and Aprons
• Non-sharp syringes

Clothes, Towels and Linen

We try to limit the amount of times we change the bed linen while your child is having treatment. If your child has an accident, the nurses will change the linen.

You should plan for your child to be in hospital for approximately three to five days, although a longer stay is sometimes necessary. The radiotherapy physics team will give you a yellow card. The card has details of your child’s treatment, any restrictions in place at the time of their discharge, the time the restrictions are applied until and the contact details for the radiotherapy physics department.

You and your child should carry this card with you at all times after leaving hospital, until the date indicated on the card. If your child attends another healthcare setting during the restriction period, the yellow card must be shown to staff.

Depending on your child’s radiation levels, they may need to avoid being in close contact with people for prolonged periods, particularly other children and pregnant individuals. Your child should not fly until they have reached a low radiation level which is determined by the radiotherapy medical physics team. It may take several days to reach this level.

Typically, a child will require a week at home before they can return to school. You must therefore not arrange any important engagements for at least two weeks after your child’s admission to hospital.

If you wish for your child’s restrictions to be lifted earlier, we may recommend that you return to the hospital to be re-monitored. The radiotherapy physics team will discuss this with you before you are discharged from the ward. If you live some distance from UCH, it may be possible for re-monitoring to take place at a local hospital, with nuclear medicine facilities, with prior arrangement.

Usually there are no major side effects from the treatment. Your child may experience some discomfort in their salivary glands, soreness in the neck, dryness and discomfort in the mouth and/or swelling of their neck and salivary glands. Some patients may also experience an altered taste sensation. If your child does experience these side effects, they should last no longer than a few days. Drinking lots of fluids after the treatment may help reduce this problem, as can chewing gum or sucking boiled sweets.

Late side effects incurred by treatment can appear to develop months or years after radioactive iodine (131 I) treatment. There is a very low risk of secondary malignancy and an increased risk of leukaemia in 0-5% of patients. This risk can increase with cumulative doses of radioactive iodine (131 I) treatment and with the use of additional external beam radiotherapy.

Patients who have had multiple radioactive iodine (131 I) treatments may also be at an increased risk of developing secondary solid malignancies. Your clinical oncologist will discuss this with you in more detail at the time of consent.

Female fertility should not be affected in the long term even after repeated doses of radioactive iodine (131 I) treatments. There may be a small risk of reduced male fertility if repeated radioactive iodine (131 I) treatments are needed. In this situation, your child can be referred for sperm banking. The MRT radiographers will discuss any issues around sex, contraception and intimacy with you and your child.

If your child received Thyrogen injections, they will continue with their thyroid hormone tablets. If they stopped taking their thyroid hormones, they will be asked to re-start their thyroid replacement tablets immediately on discharge from hospital.

You will be given an appointment for you and your child to see your doctor in clinic approximately four weeks after treatment. Your doctor will have all the results of the blood tests and post-treatment scan and will discuss the results with you.

The treatment works slowly over a period of months. Your child will have an ultrasound scan and a blood test nine-twelve months after treatment. They may also require a diagnostic radioiodine whole body scan.

Some patients may need more than one treatment. The post-treatment scan and blood tests are used to decide if any more radioactive iodine (131 I) treatment is needed.

Radiation – The shortened term for ‘ionising radiation’. It is used to describe the wave or particle emitted by a substance.

Radioactive – A term used to describe a substance that emits radiation. Radioiodine (I-131) is radioactive.

Radioisotope – A radioactive substance. For example, Iodine-131 is a radioisotope.

Half-life – As radioisotopes emit radiation they decay and become weaker. The half-life is the amount of time it takes for a radioisotope to decay to a state in which it emits only half as much radiation. The half-life for radioiodine is eight days.

µSv (microsievert) – A unit of radiation dose.

Bq (Bequerel) – A unit which describes how much radioactivity is present.

Dosemeter – A small device that is worn to measure radiation dose.

Radiation meter – An electronic device used to detect the presence of radiation and measure radiation levels.

Contamination – The presence of a radioisotope in an area it is not planned for it to be in. For example, the presence of a radioactive substance anywhere but in your child’s body or in the toilet.

Lead shield – Used to stop radiation. Since lead shields are very thick and lead is a very dense material, it stops or “absorbs” almost all of the radiation.

Ablation – The destruction of residual thyroid tissue. 131I is preferentially taken up by any thyroid tissue and destroys it with radiation.

Thyroid Stimulating Hormone – This is released by the pituitary gland to regulate the function of the thyroid. Thyroid replacement hormones, such as Levothyroxine Sodium (T4) and Liothyronine (T3), suppress TSH levels following removal of the thyroid. 

However, high TSH levels promote high uptake of 131I which is why replacement hormones are stopped pre-treatment.

Molecular Radiotherapy Team
t: 020 3447 4286
t: 020 3456 7890 bleep 1089 or 1097
e: uclh.RadiotherapyIsotopes@nhs.net

Molecular Radiotherapy Pathway Coordinator
t: 020 3447 7283

T11 North Ward
t: 020 3447 1102/ 020 3447 1188

Radiotherapy Medical Physics
t: 020 3456 7890 Bleep 2173

If you have any concerns that you would like to discuss in confidence, please contact our PALS (Patient Advice and Liaison Service) for information and advice.
t: 020 3447 3042
e: uclh.pals@nhs.net

British Thyroid Foundation
t: 01423 810093
w: www.btf-thyroid.org

Butterfly Thyroid Cancer Trust
t: 01207 545469
e: enquiries@butterfly.org.uk
w: www.butterfly.org.uk

Molecular Radiotherapy Team
t: 020 3447 4286
t: 020 3456 7890 bleep 1089 or 1097
e: uclh.RadiotherapyIsotopes@nhs.net

Molecular Radiotherapy Pathway Coordinator
t: 020 3447 7283

T11 North Ward
t: 020 3447 1102/ 020 3447 1188

Radiotherapy Medical Physics
t: 020 3456 7890 Bleep 2173

British Thyroid Association
w: www.british-thyroid-association.org

Young Lives vs Cancer (formerly CLIC Sargent)
t: 0300 330 0803
w: www.younglivesvscancer.org.uk

Teenage Cancer Trust
t: 020 7612 0370
e: hello@teenagecancertrust.org
w: www.teenagecancertrust.org

Childrens Cancer and Leukaemia Group (CCLG)
e: info@cclg.org.uk
w: www.cclg.org.uk

Macmillan Cancer Support
t: 0808 808 0000
e: cancerline@macmillan.org.uk
w: www.macmillan.org.uk

Cancer Research UK
t: 0808 800 4040
w: www.cancerresearchuk.org

Carers UK
t: 0808 808 7777
e: adviceline@carersuk.org
w: www.carersuk.org

NHS Choices
w: www.nhs.uk

UCLH cannot accept responsibility for information provided by other organisations.

Make a note of your clinicians' names and the department's contact details, for future reference.